| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.lang3; |
| |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Locale; |
| import java.util.regex.Pattern; |
| |
| /** |
| * <p>Operations on {@link java.lang.String} that are |
| * {@code null} safe.</p> |
| * |
| * <ul> |
| * <li><b>IsEmpty/IsBlank</b> |
| * - checks if a String contains text</li> |
| * <li><b>Trim/Strip</b> |
| * - removes leading and trailing whitespace</li> |
| * <li><b>Equals</b> |
| * - compares two strings null-safe</li> |
| * <li><b>startsWith</b> |
| * - check if a String starts with a prefix null-safe</li> |
| * <li><b>endsWith</b> |
| * - check if a String ends with a suffix null-safe</li> |
| * <li><b>IndexOf/LastIndexOf/Contains</b> |
| * - null-safe index-of checks |
| * <li><b>IndexOfAny/LastIndexOfAny/IndexOfAnyBut/LastIndexOfAnyBut</b> |
| * - index-of any of a set of Strings</li> |
| * <li><b>ContainsOnly/ContainsNone/ContainsAny</b> |
| * - does String contains only/none/any of these characters</li> |
| * <li><b>Substring/Left/Right/Mid</b> |
| * - null-safe substring extractions</li> |
| * <li><b>SubstringBefore/SubstringAfter/SubstringBetween</b> |
| * - substring extraction relative to other strings</li> |
| * <li><b>Split/Join</b> |
| * - splits a String into an array of substrings and vice versa</li> |
| * <li><b>Remove/Delete</b> |
| * - removes part of a String</li> |
| * <li><b>Replace/Overlay</b> |
| * - Searches a String and replaces one String with another</li> |
| * <li><b>Chomp/Chop</b> |
| * - removes the last part of a String</li> |
| * <li><b>LeftPad/RightPad/Center/Repeat</b> |
| * - pads a String</li> |
| * <li><b>UpperCase/LowerCase/SwapCase/Capitalize/Uncapitalize</b> |
| * - changes the case of a String</li> |
| * <li><b>CountMatches</b> |
| * - counts the number of occurrences of one String in another</li> |
| * <li><b>IsAlpha/IsNumeric/IsWhitespace/IsAsciiPrintable</b> |
| * - checks the characters in a String</li> |
| * <li><b>DefaultString</b> |
| * - protects against a null input String</li> |
| * <li><b>Reverse/ReverseDelimited</b> |
| * - reverses a String</li> |
| * <li><b>Abbreviate</b> |
| * - abbreviates a string using ellipsis</li> |
| * <li><b>Difference</b> |
| * - compares Strings and reports on their differences</li> |
| * <li><b>LevenshteinDistance</b> |
| * - the number of changes needed to change one String into another</li> |
| * </ul> |
| * |
| * <p>The {@code StringUtils} class defines certain words related to |
| * String handling.</p> |
| * |
| * <ul> |
| * <li>null - {@code null}</li> |
| * <li>empty - a zero-length string ({@code ""})</li> |
| * <li>space - the space character ({@code ' '}, char 32)</li> |
| * <li>whitespace - the characters defined by {@link Character#isWhitespace(char)}</li> |
| * <li>trim - the characters <= 32 as in {@link String#trim()}</li> |
| * </ul> |
| * |
| * <p>{@code StringUtils} handles {@code null} input Strings quietly. |
| * That is to say that a {@code null} input will return {@code null}. |
| * Where a {@code boolean} or {@code int} is being returned |
| * details vary by method.</p> |
| * |
| * <p>A side effect of the {@code null} handling is that a |
| * {@code NullPointerException} should be considered a bug in |
| * {@code StringUtils}.</p> |
| * |
| * <p>Methods in this class give sample code to explain their operation. |
| * The symbol {@code *} is used to indicate any input including {@code null}.</p> |
| * |
| * <p>#ThreadSafe#</p> |
| * @see java.lang.String |
| * @since 1.0 |
| * @version $Id$ |
| */ |
| //@Immutable |
| public class StringUtils { |
| // Performance testing notes (JDK 1.4, Jul03, scolebourne) |
| // Whitespace: |
| // Character.isWhitespace() is faster than WHITESPACE.indexOf() |
| // where WHITESPACE is a string of all whitespace characters |
| // |
| // Character access: |
| // String.charAt(n) versus toCharArray(), then array[n] |
| // String.charAt(n) is about 15% worse for a 10K string |
| // They are about equal for a length 50 string |
| // String.charAt(n) is about 4 times better for a length 3 string |
| // String.charAt(n) is best bet overall |
| // |
| // Append: |
| // String.concat about twice as fast as StringBuffer.append |
| // (not sure who tested this) |
| |
| /** |
| * The empty String {@code ""}. |
| * @since 2.0 |
| */ |
| public static final String EMPTY = ""; |
| |
| /** |
| * Represents a failed index search. |
| * @since 2.1 |
| */ |
| public static final int INDEX_NOT_FOUND = -1; |
| |
| /** |
| * <p>The maximum size to which the padding constant(s) can expand.</p> |
| */ |
| private static final int PAD_LIMIT = 8192; |
| |
| /** |
| * A regex pattern for recognizing blocks of whitespace characters. |
| */ |
| private static final Pattern WHITESPACE_BLOCK = Pattern.compile("\\s+"); |
| |
| /** |
| * <p>{@code StringUtils} instances should NOT be constructed in |
| * standard programming. Instead, the class should be used as |
| * {@code StringUtils.trim(" foo ");}.</p> |
| * |
| * <p>This constructor is public to permit tools that require a JavaBean |
| * instance to operate.</p> |
| */ |
| public StringUtils() { |
| super(); |
| } |
| |
| // Empty checks |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if a CharSequence is empty ("") or null.</p> |
| * |
| * <pre> |
| * StringUtils.isEmpty(null) = true |
| * StringUtils.isEmpty("") = true |
| * StringUtils.isEmpty(" ") = false |
| * StringUtils.isEmpty("bob") = false |
| * StringUtils.isEmpty(" bob ") = false |
| * </pre> |
| * |
| * <p>NOTE: This method changed in Lang version 2.0. |
| * It no longer trims the CharSequence. |
| * That functionality is available in isBlank().</p> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if the CharSequence is empty or null |
| * @since 3.0 Changed signature from isEmpty(String) to isEmpty(CharSequence) |
| */ |
| public static boolean isEmpty(CharSequence cs) { |
| return cs == null || cs.length() == 0; |
| } |
| |
| /** |
| * <p>Checks if a CharSequence is not empty ("") and not null.</p> |
| * |
| * <pre> |
| * StringUtils.isNotEmpty(null) = false |
| * StringUtils.isNotEmpty("") = false |
| * StringUtils.isNotEmpty(" ") = true |
| * StringUtils.isNotEmpty("bob") = true |
| * StringUtils.isNotEmpty(" bob ") = true |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if the CharSequence is not empty and not null |
| * @since 3.0 Changed signature from isNotEmpty(String) to isNotEmpty(CharSequence) |
| */ |
| public static boolean isNotEmpty(CharSequence cs) { |
| return !StringUtils.isEmpty(cs); |
| } |
| |
| /** |
| * <p>Checks if a CharSequence is whitespace, empty ("") or null.</p> |
| * |
| * <pre> |
| * StringUtils.isBlank(null) = true |
| * StringUtils.isBlank("") = true |
| * StringUtils.isBlank(" ") = true |
| * StringUtils.isBlank("bob") = false |
| * StringUtils.isBlank(" bob ") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if the CharSequence is null, empty or whitespace |
| * @since 2.0 |
| * @since 3.0 Changed signature from isBlank(String) to isBlank(CharSequence) |
| */ |
| public static boolean isBlank(CharSequence cs) { |
| int strLen; |
| if (cs == null || (strLen = cs.length()) == 0) { |
| return true; |
| } |
| for (int i = 0; i < strLen; i++) { |
| if ((Character.isWhitespace(cs.charAt(i)) == false)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if a CharSequence is not empty (""), not null and not whitespace only.</p> |
| * |
| * <pre> |
| * StringUtils.isNotBlank(null) = false |
| * StringUtils.isNotBlank("") = false |
| * StringUtils.isNotBlank(" ") = false |
| * StringUtils.isNotBlank("bob") = true |
| * StringUtils.isNotBlank(" bob ") = true |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if the CharSequence is |
| * not empty and not null and not whitespace |
| * @since 2.0 |
| * @since 3.0 Changed signature from isNotBlank(String) to isNotBlank(CharSequence) |
| */ |
| public static boolean isNotBlank(CharSequence cs) { |
| return !StringUtils.isBlank(cs); |
| } |
| |
| // Trim |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Removes control characters (char <= 32) from both |
| * ends of this String, handling {@code null} by returning |
| * {@code null}.</p> |
| * |
| * <p>The String is trimmed using {@link String#trim()}. |
| * Trim removes start and end characters <= 32. |
| * To strip whitespace use {@link #strip(String)}.</p> |
| * |
| * <p>To trim your choice of characters, use the |
| * {@link #strip(String, String)} methods.</p> |
| * |
| * <pre> |
| * StringUtils.trim(null) = null |
| * StringUtils.trim("") = "" |
| * StringUtils.trim(" ") = "" |
| * StringUtils.trim("abc") = "abc" |
| * StringUtils.trim(" abc ") = "abc" |
| * </pre> |
| * |
| * @param str the String to be trimmed, may be null |
| * @return the trimmed string, {@code null} if null String input |
| */ |
| public static String trim(String str) { |
| return str == null ? null : str.trim(); |
| } |
| |
| /** |
| * <p>Removes control characters (char <= 32) from both |
| * ends of this String returning {@code null} if the String is |
| * empty ("") after the trim or if it is {@code null}. |
| * |
| * <p>The String is trimmed using {@link String#trim()}. |
| * Trim removes start and end characters <= 32. |
| * To strip whitespace use {@link #stripToNull(String)}.</p> |
| * |
| * <pre> |
| * StringUtils.trimToNull(null) = null |
| * StringUtils.trimToNull("") = null |
| * StringUtils.trimToNull(" ") = null |
| * StringUtils.trimToNull("abc") = "abc" |
| * StringUtils.trimToNull(" abc ") = "abc" |
| * </pre> |
| * |
| * @param str the String to be trimmed, may be null |
| * @return the trimmed String, |
| * {@code null} if only chars <= 32, empty or null String input |
| * @since 2.0 |
| */ |
| public static String trimToNull(String str) { |
| String ts = trim(str); |
| return isEmpty(ts) ? null : ts; |
| } |
| |
| /** |
| * <p>Removes control characters (char <= 32) from both |
| * ends of this String returning an empty String ("") if the String |
| * is empty ("") after the trim or if it is {@code null}. |
| * |
| * <p>The String is trimmed using {@link String#trim()}. |
| * Trim removes start and end characters <= 32. |
| * To strip whitespace use {@link #stripToEmpty(String)}.</p> |
| * |
| * <pre> |
| * StringUtils.trimToEmpty(null) = "" |
| * StringUtils.trimToEmpty("") = "" |
| * StringUtils.trimToEmpty(" ") = "" |
| * StringUtils.trimToEmpty("abc") = "abc" |
| * StringUtils.trimToEmpty(" abc ") = "abc" |
| * </pre> |
| * |
| * @param str the String to be trimmed, may be null |
| * @return the trimmed String, or an empty String if {@code null} input |
| * @since 2.0 |
| */ |
| public static String trimToEmpty(String str) { |
| return str == null ? EMPTY : str.trim(); |
| } |
| |
| // Stripping |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Strips whitespace from the start and end of a String.</p> |
| * |
| * <p>This is similar to {@link #trim(String)} but removes whitespace. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.strip(null) = null |
| * StringUtils.strip("") = "" |
| * StringUtils.strip(" ") = "" |
| * StringUtils.strip("abc") = "abc" |
| * StringUtils.strip(" abc") = "abc" |
| * StringUtils.strip("abc ") = "abc" |
| * StringUtils.strip(" abc ") = "abc" |
| * StringUtils.strip(" ab c ") = "ab c" |
| * </pre> |
| * |
| * @param str the String to remove whitespace from, may be null |
| * @return the stripped String, {@code null} if null String input |
| */ |
| public static String strip(String str) { |
| return strip(str, null); |
| } |
| |
| /** |
| * <p>Strips whitespace from the start and end of a String returning |
| * {@code null} if the String is empty ("") after the strip.</p> |
| * |
| * <p>This is similar to {@link #trimToNull(String)} but removes whitespace. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.stripToNull(null) = null |
| * StringUtils.stripToNull("") = null |
| * StringUtils.stripToNull(" ") = null |
| * StringUtils.stripToNull("abc") = "abc" |
| * StringUtils.stripToNull(" abc") = "abc" |
| * StringUtils.stripToNull("abc ") = "abc" |
| * StringUtils.stripToNull(" abc ") = "abc" |
| * StringUtils.stripToNull(" ab c ") = "ab c" |
| * </pre> |
| * |
| * @param str the String to be stripped, may be null |
| * @return the stripped String, |
| * {@code null} if whitespace, empty or null String input |
| * @since 2.0 |
| */ |
| public static String stripToNull(String str) { |
| if (str == null) { |
| return null; |
| } |
| str = strip(str, null); |
| return str.length() == 0 ? null : str; |
| } |
| |
| /** |
| * <p>Strips whitespace from the start and end of a String returning |
| * an empty String if {@code null} input.</p> |
| * |
| * <p>This is similar to {@link #trimToEmpty(String)} but removes whitespace. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.stripToEmpty(null) = "" |
| * StringUtils.stripToEmpty("") = "" |
| * StringUtils.stripToEmpty(" ") = "" |
| * StringUtils.stripToEmpty("abc") = "abc" |
| * StringUtils.stripToEmpty(" abc") = "abc" |
| * StringUtils.stripToEmpty("abc ") = "abc" |
| * StringUtils.stripToEmpty(" abc ") = "abc" |
| * StringUtils.stripToEmpty(" ab c ") = "ab c" |
| * </pre> |
| * |
| * @param str the String to be stripped, may be null |
| * @return the trimmed String, or an empty String if {@code null} input |
| * @since 2.0 |
| */ |
| public static String stripToEmpty(String str) { |
| return str == null ? EMPTY : strip(str, null); |
| } |
| |
| /** |
| * <p>Strips any of a set of characters from the start and end of a String. |
| * This is similar to {@link String#trim()} but allows the characters |
| * to be stripped to be controlled.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * An empty string ("") input returns the empty string.</p> |
| * |
| * <p>If the stripChars String is {@code null}, whitespace is |
| * stripped as defined by {@link Character#isWhitespace(char)}. |
| * Alternatively use {@link #strip(String)}.</p> |
| * |
| * <pre> |
| * StringUtils.strip(null, *) = null |
| * StringUtils.strip("", *) = "" |
| * StringUtils.strip("abc", null) = "abc" |
| * StringUtils.strip(" abc", null) = "abc" |
| * StringUtils.strip("abc ", null) = "abc" |
| * StringUtils.strip(" abc ", null) = "abc" |
| * StringUtils.strip(" abcyx", "xyz") = " abc" |
| * </pre> |
| * |
| * @param str the String to remove characters from, may be null |
| * @param stripChars the characters to remove, null treated as whitespace |
| * @return the stripped String, {@code null} if null String input |
| */ |
| public static String strip(String str, String stripChars) { |
| if (isEmpty(str)) { |
| return str; |
| } |
| str = stripStart(str, stripChars); |
| return stripEnd(str, stripChars); |
| } |
| |
| /** |
| * <p>Strips any of a set of characters from the start of a String.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * An empty string ("") input returns the empty string.</p> |
| * |
| * <p>If the stripChars String is {@code null}, whitespace is |
| * stripped as defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.stripStart(null, *) = null |
| * StringUtils.stripStart("", *) = "" |
| * StringUtils.stripStart("abc", "") = "abc" |
| * StringUtils.stripStart("abc", null) = "abc" |
| * StringUtils.stripStart(" abc", null) = "abc" |
| * StringUtils.stripStart("abc ", null) = "abc " |
| * StringUtils.stripStart(" abc ", null) = "abc " |
| * StringUtils.stripStart("yxabc ", "xyz") = "abc " |
| * </pre> |
| * |
| * @param str the String to remove characters from, may be null |
| * @param stripChars the characters to remove, null treated as whitespace |
| * @return the stripped String, {@code null} if null String input |
| */ |
| public static String stripStart(String str, String stripChars) { |
| int strLen; |
| if (str == null || (strLen = str.length()) == 0) { |
| return str; |
| } |
| int start = 0; |
| if (stripChars == null) { |
| while ((start != strLen) && Character.isWhitespace(str.charAt(start))) { |
| start++; |
| } |
| } else if (stripChars.length() == 0) { |
| return str; |
| } else { |
| while ((start != strLen) && (stripChars.indexOf(str.charAt(start)) != INDEX_NOT_FOUND)) { |
| start++; |
| } |
| } |
| return str.substring(start); |
| } |
| |
| /** |
| * <p>Strips any of a set of characters from the end of a String.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * An empty string ("") input returns the empty string.</p> |
| * |
| * <p>If the stripChars String is {@code null}, whitespace is |
| * stripped as defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.stripEnd(null, *) = null |
| * StringUtils.stripEnd("", *) = "" |
| * StringUtils.stripEnd("abc", "") = "abc" |
| * StringUtils.stripEnd("abc", null) = "abc" |
| * StringUtils.stripEnd(" abc", null) = " abc" |
| * StringUtils.stripEnd("abc ", null) = "abc" |
| * StringUtils.stripEnd(" abc ", null) = " abc" |
| * StringUtils.stripEnd(" abcyx", "xyz") = " abc" |
| * StringUtils.stripEnd("120.00", ".0") = "12" |
| * </pre> |
| * |
| * @param str the String to remove characters from, may be null |
| * @param stripChars the set of characters to remove, null treated as whitespace |
| * @return the stripped String, {@code null} if null String input |
| */ |
| public static String stripEnd(String str, String stripChars) { |
| int end; |
| if (str == null || (end = str.length()) == 0) { |
| return str; |
| } |
| |
| if (stripChars == null) { |
| while ((end != 0) && Character.isWhitespace(str.charAt(end - 1))) { |
| end--; |
| } |
| } else if (stripChars.length() == 0) { |
| return str; |
| } else { |
| while ((end != 0) && (stripChars.indexOf(str.charAt(end - 1)) != INDEX_NOT_FOUND)) { |
| end--; |
| } |
| } |
| return str.substring(0, end); |
| } |
| |
| // StripAll |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Strips whitespace from the start and end of every String in an array. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <p>A new array is returned each time, except for length zero. |
| * A {@code null} array will return {@code null}. |
| * An empty array will return itself. |
| * A {@code null} array entry will be ignored.</p> |
| * |
| * <pre> |
| * StringUtils.stripAll(null) = null |
| * StringUtils.stripAll([]) = [] |
| * StringUtils.stripAll(["abc", " abc"]) = ["abc", "abc"] |
| * StringUtils.stripAll(["abc ", null]) = ["abc", null] |
| * </pre> |
| * |
| * @param strs the array to remove whitespace from, may be null |
| * @return the stripped Strings, {@code null} if null array input |
| */ |
| public static String[] stripAll(String... strs) { |
| return stripAll(strs, null); |
| } |
| |
| /** |
| * <p>Strips any of a set of characters from the start and end of every |
| * String in an array.</p> |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <p>A new array is returned each time, except for length zero. |
| * A {@code null} array will return {@code null}. |
| * An empty array will return itself. |
| * A {@code null} array entry will be ignored. |
| * A {@code null} stripChars will strip whitespace as defined by |
| * {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.stripAll(null, *) = null |
| * StringUtils.stripAll([], *) = [] |
| * StringUtils.stripAll(["abc", " abc"], null) = ["abc", "abc"] |
| * StringUtils.stripAll(["abc ", null], null) = ["abc", null] |
| * StringUtils.stripAll(["abc ", null], "yz") = ["abc ", null] |
| * StringUtils.stripAll(["yabcz", null], "yz") = ["abc", null] |
| * </pre> |
| * |
| * @param strs the array to remove characters from, may be null |
| * @param stripChars the characters to remove, null treated as whitespace |
| * @return the stripped Strings, {@code null} if null array input |
| */ |
| public static String[] stripAll(String[] strs, String stripChars) { |
| int strsLen; |
| if (strs == null || (strsLen = strs.length) == 0) { |
| return strs; |
| } |
| String[] newArr = new String[strsLen]; |
| for (int i = 0; i < strsLen; i++) { |
| newArr[i] = strip(strs[i], stripChars); |
| } |
| return newArr; |
| } |
| |
| /** |
| * <p>Removes diacritics (~= accents) from a string. The case will not be altered.</p> |
| * <p>For instance, 'à' will be replaced by 'a'.</p> |
| * <p>Note that ligatures will be left as is.</p> |
| * |
| * <p>This method will use the first available implementation of: |
| * Java 6's {@link java.text.Normalizer}, Java 1.3–1.5's {@code sun.text.Normalizer}</p> |
| * |
| * <pre> |
| * StringUtils.stripAccents(null) = null |
| * StringUtils.stripAccents("") = "" |
| * StringUtils.stripAccents("control") = "control" |
| * StringUtils.stripAccents("éclair") = "eclair" |
| * </pre> |
| * |
| * @param input String to be stripped |
| * @return input text with diacritics removed |
| * |
| * @since 3.0 |
| */ |
| // See also Lucene's ASCIIFoldingFilter (Lucene 2.9) that replaces accented characters by their unaccented equivalent (and uncommitted bug fix: https://issues.apache.org/jira/browse/LUCENE-1343?focusedCommentId=12858907&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_12858907). |
| public static String stripAccents(String input) { |
| if(input == null) { |
| return null; |
| } |
| try { |
| String result = null; |
| if (java6Available) { |
| result = removeAccentsJava6(input); |
| } else if (sunAvailable) { |
| result = removeAccentsSUN(input); |
| } else { |
| throw new UnsupportedOperationException( |
| "The stripAccents(CharSequence) method requires at least Java 1.6 or a Sun JVM"); |
| } |
| // Note that none of the above methods correctly remove ligatures... |
| return result; |
| } catch(IllegalArgumentException iae) { |
| throw new RuntimeException("IllegalArgumentException occurred", iae); |
| } catch(IllegalAccessException iae) { |
| throw new RuntimeException("IllegalAccessException occurred", iae); |
| } catch(InvocationTargetException ite) { |
| throw new RuntimeException("InvocationTargetException occurred", ite); |
| } catch(SecurityException se) { |
| throw new RuntimeException("SecurityException occurred", se); |
| } |
| } |
| |
| /** |
| * Use {@code java.text.Normalizer#normalize(CharSequence, Normalizer.Form)} |
| * (but be careful, this class exists in Java 1.3, with an entirely different meaning!) |
| * |
| * @param text the text to be processed |
| * @return the processed string |
| * @throws IllegalAccessException may be thrown by a reflection call |
| * @throws InvocationTargetException if a reflection call throws an exception |
| * @throws IllegalStateException if the {@code Normalizer} class is not available |
| */ |
| private static String removeAccentsJava6(CharSequence text) |
| throws IllegalAccessException, InvocationTargetException { |
| /* |
| String decomposed = java.text.Normalizer.normalize(CharSequence, Normalizer.Form.NFD); |
| return java6Pattern.matcher(decomposed).replaceAll("");//$NON-NLS-1$ |
| */ |
| if (!java6Available || java6NormalizerFormNFD == null) { |
| throw new IllegalStateException("java.text.Normalizer is not available"); |
| } |
| String result; |
| result = (String) java6NormalizeMethod.invoke(null, new Object[] {text, java6NormalizerFormNFD}); |
| result = java6Pattern.matcher(result).replaceAll("");//$NON-NLS-1$ |
| return result; |
| } |
| |
| /** |
| * Use {@code sun.text.Normalizer#decompose(String, boolean, int)} |
| * |
| * @param text the text to be processed |
| * @return the processed string |
| * @throws IllegalAccessException may be thrown by a reflection call |
| * @throws InvocationTargetException if a reflection call throws an exception |
| * @throws IllegalStateException if the {@code Normalizer} class is not available |
| */ |
| private static String removeAccentsSUN(CharSequence text) |
| throws IllegalAccessException, InvocationTargetException { |
| /* |
| String decomposed = sun.text.Normalizer.decompose(text, false, 0); |
| return sunPattern.matcher(decomposed).replaceAll("");//$NON-NLS-1$ |
| */ |
| if (! sunAvailable) { |
| throw new IllegalStateException("sun.text.Normalizer is not available"); |
| } |
| String result; |
| result = (String) sunDecomposeMethod.invoke(null, new Object[] {text, Boolean.FALSE, Integer.valueOf(0)}); |
| result = sunPattern.matcher(result).replaceAll("");//$NON-NLS-1$ |
| return result; |
| } |
| |
| // SUN internal, Java 1.3 -> Java 5 |
| private static boolean sunAvailable = false; |
| private static Method sunDecomposeMethod = null; |
| private static final Pattern sunPattern = Pattern.compile("\\p{InCombiningDiacriticalMarks}+");//$NON-NLS-1$ |
| // Java 6+ |
| private static boolean java6Available = false; |
| private static Method java6NormalizeMethod = null; |
| private static Object java6NormalizerFormNFD = null; |
| private static final Pattern java6Pattern = sunPattern; |
| |
| static { |
| try { |
| // java.text.Normalizer.normalize(CharSequence, Normalizer.Form.NFD); |
| // Be careful not to get Java 1.3 java.text.Normalizer! |
| Class<?> normalizerFormClass = Thread.currentThread().getContextClassLoader() |
| .loadClass("java.text.Normalizer$Form");//$NON-NLS-1$ |
| java6NormalizerFormNFD = normalizerFormClass.getField("NFD").get(null);//$NON-NLS-1$ |
| Class<?> normalizerClass = Thread.currentThread().getContextClassLoader() |
| .loadClass("java.text.Normalizer");//$NON-NLS-1$ |
| java6NormalizeMethod = normalizerClass.getMethod("normalize", |
| new Class[] {CharSequence.class, normalizerFormClass});//$NON-NLS-1$ |
| java6Available = true; |
| } catch (ClassNotFoundException e) { |
| java6Available = false; |
| } catch (NoSuchFieldException e) { |
| java6Available = false; |
| } catch (IllegalAccessException e) { |
| java6Available = false; |
| } catch (NoSuchMethodException e) { |
| java6Available = false; |
| } |
| |
| try { |
| // sun.text.Normalizer.decompose(text, false, 0); |
| Class<?> normalizerClass = Thread.currentThread().getContextClassLoader() |
| .loadClass("sun.text.Normalizer");//$NON-NLS-1$ |
| sunDecomposeMethod = normalizerClass.getMethod("decompose", |
| new Class[] {String.class, Boolean.TYPE, Integer.TYPE});//$NON-NLS-1$ |
| sunAvailable = true; |
| } catch (ClassNotFoundException e) { |
| sunAvailable = false; |
| } catch (NoSuchMethodException e) { |
| sunAvailable = false; |
| } |
| } |
| |
| // Equals |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Compares two CharSequences, returning {@code true} if they are equal.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered to be equal. The comparison is case sensitive.</p> |
| * |
| * <pre> |
| * StringUtils.equals(null, null) = true |
| * StringUtils.equals(null, "abc") = false |
| * StringUtils.equals("abc", null) = false |
| * StringUtils.equals("abc", "abc") = true |
| * StringUtils.equals("abc", "ABC") = false |
| * </pre> |
| * |
| * @see java.lang.String#equals(Object) |
| * @param cs1 the first CharSequence, may be null |
| * @param cs2 the second CharSequence, may be null |
| * @return {@code true} if the CharSequences are equal, case sensitive, or |
| * both {@code null} |
| * @since 3.0 Changed signature from equals(String, String) to equals(CharSequence, CharSequence) |
| */ |
| public static boolean equals(CharSequence cs1, CharSequence cs2) { |
| return cs1 == null ? cs2 == null : cs1.equals(cs2); |
| } |
| |
| /** |
| * <p>Compares two CharSequences, returning {@code true} if they are equal ignoring |
| * the case.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered equal. Comparison is case insensitive.</p> |
| * |
| * <pre> |
| * StringUtils.equalsIgnoreCase(null, null) = true |
| * StringUtils.equalsIgnoreCase(null, "abc") = false |
| * StringUtils.equalsIgnoreCase("abc", null) = false |
| * StringUtils.equalsIgnoreCase("abc", "abc") = true |
| * StringUtils.equalsIgnoreCase("abc", "ABC") = true |
| * </pre> |
| * |
| * @param str1 the first CharSequence, may be null |
| * @param str2 the second CharSequence, may be null |
| * @return {@code true} if the CharSequence are equal, case insensitive, or |
| * both {@code null} |
| * @since 3.0 Changed signature from equalsIgnoreCase(String, String) to equalsIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static boolean equalsIgnoreCase(CharSequence str1, CharSequence str2) { |
| if (str1 == null || str2 == null) { |
| return str1 == str2; |
| } else { |
| return CharSequenceUtils.regionMatches(str1, true, 0, str2, 0, Math.max(str1.length(), str2.length())); |
| } |
| } |
| |
| // IndexOf |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Finds the first index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#indexOf(int, int)} if possible.</p> |
| * |
| * <p>A {@code null} or empty ("") CharSequence will return {@code INDEX_NOT_FOUND (-1)}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOf(null, *) = -1 |
| * StringUtils.indexOf("", *) = -1 |
| * StringUtils.indexOf("aabaabaa", 'a') = 0 |
| * StringUtils.indexOf("aabaabaa", 'b') = 2 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChar the character to find |
| * @return the first index of the search character, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOf(String, int) to indexOf(CharSequence, int) |
| */ |
| public static int indexOf(CharSequence seq, int searchChar) { |
| if (isEmpty(seq)) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.indexOf(seq, searchChar, 0); |
| } |
| |
| /** |
| * <p>Finds the first index within a CharSequence from a start position, |
| * handling {@code null}. |
| * This method uses {@link String#indexOf(int, int)} if possible.</p> |
| * |
| * <p>A {@code null} or empty ("") CharSequence will return {@code (INDEX_NOT_FOUND) -1}. |
| * A negative start position is treated as zero. |
| * A start position greater than the string length returns {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOf(null, *, *) = -1 |
| * StringUtils.indexOf("", *, *) = -1 |
| * StringUtils.indexOf("aabaabaa", 'b', 0) = 2 |
| * StringUtils.indexOf("aabaabaa", 'b', 3) = 5 |
| * StringUtils.indexOf("aabaabaa", 'b', 9) = -1 |
| * StringUtils.indexOf("aabaabaa", 'b', -1) = 2 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChar the character to find |
| * @param startPos the start position, negative treated as zero |
| * @return the first index of the search character, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOf(String, int, int) to indexOf(CharSequence, int, int) |
| */ |
| public static int indexOf(CharSequence seq, int searchChar, int startPos) { |
| if (isEmpty(seq)) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.indexOf(seq, searchChar, startPos); |
| } |
| |
| /** |
| * <p>Finds the first index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#indexOf(String, int)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOf(null, *) = -1 |
| * StringUtils.indexOf(*, null) = -1 |
| * StringUtils.indexOf("", "") = 0 |
| * StringUtils.indexOf("", *) = -1 (except when * = "") |
| * StringUtils.indexOf("aabaabaa", "a") = 0 |
| * StringUtils.indexOf("aabaabaa", "b") = 2 |
| * StringUtils.indexOf("aabaabaa", "ab") = 1 |
| * StringUtils.indexOf("aabaabaa", "") = 0 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchSeq the CharSequence to find, may be null |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOf(String, String) to indexOf(CharSequence, CharSequence) |
| */ |
| public static int indexOf(CharSequence seq, CharSequence searchSeq) { |
| if (seq == null || searchSeq == null) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.indexOf(seq, searchSeq, 0); |
| } |
| |
| /** |
| * <p>Finds the first index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#indexOf(String, int)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position is treated as zero. |
| * An empty ("") search CharSequence always matches. |
| * A start position greater than the string length only matches |
| * an empty search CharSequence.</p> |
| * |
| * <pre> |
| * StringUtils.indexOf(null, *, *) = -1 |
| * StringUtils.indexOf(*, null, *) = -1 |
| * StringUtils.indexOf("", "", 0) = 0 |
| * StringUtils.indexOf("", *, 0) = -1 (except when * = "") |
| * StringUtils.indexOf("aabaabaa", "a", 0) = 0 |
| * StringUtils.indexOf("aabaabaa", "b", 0) = 2 |
| * StringUtils.indexOf("aabaabaa", "ab", 0) = 1 |
| * StringUtils.indexOf("aabaabaa", "b", 3) = 5 |
| * StringUtils.indexOf("aabaabaa", "b", 9) = -1 |
| * StringUtils.indexOf("aabaabaa", "b", -1) = 2 |
| * StringUtils.indexOf("aabaabaa", "", 2) = 2 |
| * StringUtils.indexOf("abc", "", 9) = 3 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchSeq the CharSequence to find, may be null |
| * @param startPos the start position, negative treated as zero |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOf(String, String, int) to indexOf(CharSequence, CharSequence, int) |
| */ |
| public static int indexOf(CharSequence seq, CharSequence searchSeq, int startPos) { |
| if (seq == null || searchSeq == null) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.indexOf(seq, searchSeq, startPos); |
| } |
| |
| /** |
| * <p>Finds the n-th index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#indexOf(String)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.ordinalIndexOf(null, *, *) = -1 |
| * StringUtils.ordinalIndexOf(*, null, *) = -1 |
| * StringUtils.ordinalIndexOf("", "", *) = 0 |
| * StringUtils.ordinalIndexOf("aabaabaa", "a", 1) = 0 |
| * StringUtils.ordinalIndexOf("aabaabaa", "a", 2) = 1 |
| * StringUtils.ordinalIndexOf("aabaabaa", "b", 1) = 2 |
| * StringUtils.ordinalIndexOf("aabaabaa", "b", 2) = 5 |
| * StringUtils.ordinalIndexOf("aabaabaa", "ab", 1) = 1 |
| * StringUtils.ordinalIndexOf("aabaabaa", "ab", 2) = 4 |
| * StringUtils.ordinalIndexOf("aabaabaa", "", 1) = 0 |
| * StringUtils.ordinalIndexOf("aabaabaa", "", 2) = 0 |
| * </pre> |
| * |
| * <p>Note that 'head(CharSequence str, int n)' may be implemented as: </p> |
| * |
| * <pre> |
| * str.substring(0, lastOrdinalIndexOf(str, "\n", n)) |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @param ordinal the n-th {@code searchStr} to find |
| * @return the n-th index of the search CharSequence, |
| * {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input |
| * @since 2.1 |
| * @since 3.0 Changed signature from ordinalIndexOf(String, String, int) to ordinalIndexOf(CharSequence, CharSequence, int) |
| */ |
| public static int ordinalIndexOf(CharSequence str, CharSequence searchStr, int ordinal) { |
| return ordinalIndexOf(str, searchStr, ordinal, false); |
| } |
| |
| /** |
| * <p>Finds the n-th index within a String, handling {@code null}. |
| * This method uses {@link String#indexOf(String)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}.</p> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @param ordinal the n-th {@code searchStr} to find |
| * @param lastIndex true if lastOrdinalIndexOf() otherwise false if ordinalIndexOf() |
| * @return the n-th index of the search CharSequence, |
| * {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input |
| */ |
| // Shared code between ordinalIndexOf(String,String,int) and lastOrdinalIndexOf(String,String,int) |
| private static int ordinalIndexOf(CharSequence str, CharSequence searchStr, int ordinal, boolean lastIndex) { |
| if (str == null || searchStr == null || ordinal <= 0) { |
| return INDEX_NOT_FOUND; |
| } |
| if (searchStr.length() == 0) { |
| return lastIndex ? str.length() : 0; |
| } |
| int found = 0; |
| int index = lastIndex ? str.length() : INDEX_NOT_FOUND; |
| do { |
| if (lastIndex) { |
| index = CharSequenceUtils.lastIndexOf(str, searchStr, index - 1); |
| } else { |
| index = CharSequenceUtils.indexOf(str, searchStr, index + 1); |
| } |
| if (index < 0) { |
| return index; |
| } |
| found++; |
| } while (found < ordinal); |
| return index; |
| } |
| |
| /** |
| * <p>Case in-sensitive find of the first index within a CharSequence.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position is treated as zero. |
| * An empty ("") search CharSequence always matches. |
| * A start position greater than the string length only matches |
| * an empty search CharSequence.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfIgnoreCase(null, *) = -1 |
| * StringUtils.indexOfIgnoreCase(*, null) = -1 |
| * StringUtils.indexOfIgnoreCase("", "") = 0 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "a") = 0 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "b") = 2 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "ab") = 1 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.5 |
| * @since 3.0 Changed signature from indexOfIgnoreCase(String, String) to indexOfIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static int indexOfIgnoreCase(CharSequence str, CharSequence searchStr) { |
| return indexOfIgnoreCase(str, searchStr, 0); |
| } |
| |
| /** |
| * <p>Case in-sensitive find of the first index within a CharSequence |
| * from the specified position.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position is treated as zero. |
| * An empty ("") search CharSequence always matches. |
| * A start position greater than the string length only matches |
| * an empty search CharSequence.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfIgnoreCase(null, *, *) = -1 |
| * StringUtils.indexOfIgnoreCase(*, null, *) = -1 |
| * StringUtils.indexOfIgnoreCase("", "", 0) = 0 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "A", 0) = 0 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 0) = 2 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "AB", 0) = 1 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 3) = 5 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 9) = -1 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "B", -1) = 2 |
| * StringUtils.indexOfIgnoreCase("aabaabaa", "", 2) = 2 |
| * StringUtils.indexOfIgnoreCase("abc", "", 9) = 3 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @param startPos the start position, negative treated as zero |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.5 |
| * @since 3.0 Changed signature from indexOfIgnoreCase(String, String, int) to indexOfIgnoreCase(CharSequence, CharSequence, int) |
| */ |
| public static int indexOfIgnoreCase(CharSequence str, CharSequence searchStr, int startPos) { |
| if (str == null || searchStr == null) { |
| return INDEX_NOT_FOUND; |
| } |
| if (startPos < 0) { |
| startPos = 0; |
| } |
| int endLimit = (str.length() - searchStr.length()) + 1; |
| if (startPos > endLimit) { |
| return INDEX_NOT_FOUND; |
| } |
| if (searchStr.length() == 0) { |
| return startPos; |
| } |
| for (int i = startPos; i < endLimit; i++) { |
| if (CharSequenceUtils.regionMatches(str, true, i, searchStr, 0, searchStr.length())) { |
| return i; |
| } |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| // LastIndexOf |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Finds the last index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#lastIndexOf(int)} if possible.</p> |
| * |
| * <p>A {@code null} or empty ("") CharSequence will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOf(null, *) = -1 |
| * StringUtils.lastIndexOf("", *) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", 'a') = 7 |
| * StringUtils.lastIndexOf("aabaabaa", 'b') = 5 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChar the character to find |
| * @return the last index of the search character, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from lastIndexOf(String, int) to lastIndexOf(CharSequence, int) |
| */ |
| public static int lastIndexOf(CharSequence seq, int searchChar) { |
| if (isEmpty(seq)) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.lastIndexOf(seq, searchChar, seq.length()); |
| } |
| |
| /** |
| * <p>Finds the last index within a CharSequence from a start position, |
| * handling {@code null}. |
| * This method uses {@link String#lastIndexOf(int, int)} if possible.</p> |
| * |
| * <p>A {@code null} or empty ("") CharSequence will return {@code -1}. |
| * A negative start position returns {@code -1}. |
| * A start position greater than the string length searches the whole string.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOf(null, *, *) = -1 |
| * StringUtils.lastIndexOf("", *, *) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", 'b', 8) = 5 |
| * StringUtils.lastIndexOf("aabaabaa", 'b', 4) = 2 |
| * StringUtils.lastIndexOf("aabaabaa", 'b', 0) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", 'b', 9) = 5 |
| * StringUtils.lastIndexOf("aabaabaa", 'b', -1) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", 'a', 0) = 0 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChar the character to find |
| * @param startPos the start position |
| * @return the last index of the search character, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from lastIndexOf(String, int, int) to lastIndexOf(CharSequence, int, int) |
| */ |
| public static int lastIndexOf(CharSequence seq, int searchChar, int startPos) { |
| if (isEmpty(seq)) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.lastIndexOf(seq, searchChar, startPos); |
| } |
| |
| /** |
| * <p>Finds the last index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#lastIndexOf(String)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOf(null, *) = -1 |
| * StringUtils.lastIndexOf(*, null) = -1 |
| * StringUtils.lastIndexOf("", "") = 0 |
| * StringUtils.lastIndexOf("aabaabaa", "a") = 7 |
| * StringUtils.lastIndexOf("aabaabaa", "b") = 5 |
| * StringUtils.lastIndexOf("aabaabaa", "ab") = 4 |
| * StringUtils.lastIndexOf("aabaabaa", "") = 8 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchSeq the CharSequence to find, may be null |
| * @return the last index of the search String, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from lastIndexOf(String, String) to lastIndexOf(CharSequence, CharSequence) |
| */ |
| public static int lastIndexOf(CharSequence seq, CharSequence searchSeq) { |
| if (seq == null || searchSeq == null) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.lastIndexOf(seq, searchSeq, seq.length()); |
| } |
| |
| /** |
| * <p>Finds the n-th last index within a String, handling {@code null}. |
| * This method uses {@link String#lastIndexOf(String)}.</p> |
| * |
| * <p>A {@code null} String will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.lastOrdinalIndexOf(null, *, *) = -1 |
| * StringUtils.lastOrdinalIndexOf(*, null, *) = -1 |
| * StringUtils.lastOrdinalIndexOf("", "", *) = 0 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "a", 1) = 7 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "a", 2) = 6 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "b", 1) = 5 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "b", 2) = 2 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "ab", 1) = 4 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "ab", 2) = 1 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "", 1) = 8 |
| * StringUtils.lastOrdinalIndexOf("aabaabaa", "", 2) = 8 |
| * </pre> |
| * |
| * <p>Note that 'tail(CharSequence str, int n)' may be implemented as: </p> |
| * |
| * <pre> |
| * str.substring(lastOrdinalIndexOf(str, "\n", n) + 1) |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @param ordinal the n-th last {@code searchStr} to find |
| * @return the n-th last index of the search CharSequence, |
| * {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input |
| * @since 2.5 |
| * @since 3.0 Changed signature from lastOrdinalIndexOf(String, String, int) to lastOrdinalIndexOf(CharSequence, CharSequence, int) |
| */ |
| public static int lastOrdinalIndexOf(CharSequence str, CharSequence searchStr, int ordinal) { |
| return ordinalIndexOf(str, searchStr, ordinal, true); |
| } |
| |
| /** |
| * <p>Finds the first index within a CharSequence, handling {@code null}. |
| * This method uses {@link String#lastIndexOf(String, int)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position returns {@code -1}. |
| * An empty ("") search CharSequence always matches unless the start position is negative. |
| * A start position greater than the string length searches the whole string.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOf(null, *, *) = -1 |
| * StringUtils.lastIndexOf(*, null, *) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", "a", 8) = 7 |
| * StringUtils.lastIndexOf("aabaabaa", "b", 8) = 5 |
| * StringUtils.lastIndexOf("aabaabaa", "ab", 8) = 4 |
| * StringUtils.lastIndexOf("aabaabaa", "b", 9) = 5 |
| * StringUtils.lastIndexOf("aabaabaa", "b", -1) = -1 |
| * StringUtils.lastIndexOf("aabaabaa", "a", 0) = 0 |
| * StringUtils.lastIndexOf("aabaabaa", "b", 0) = -1 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchSeq the CharSequence to find, may be null |
| * @param startPos the start position, negative treated as zero |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from lastIndexOf(String, String, int) to lastIndexOf(CharSequence, CharSequence, int) |
| */ |
| public static int lastIndexOf(CharSequence seq, CharSequence searchSeq, int startPos) { |
| if (seq == null || searchSeq == null) { |
| return INDEX_NOT_FOUND; |
| } |
| return CharSequenceUtils.lastIndexOf(seq, searchSeq, startPos); |
| } |
| |
| /** |
| * <p>Case in-sensitive find of the last index within a CharSequence.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position returns {@code -1}. |
| * An empty ("") search CharSequence always matches unless the start position is negative. |
| * A start position greater than the string length searches the whole string.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOfIgnoreCase(null, *) = -1 |
| * StringUtils.lastIndexOfIgnoreCase(*, null) = -1 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A") = 7 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B") = 5 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "AB") = 4 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} string input |
| * @since 2.5 |
| * @since 3.0 Changed signature from lastIndexOfIgnoreCase(String, String) to lastIndexOfIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static int lastIndexOfIgnoreCase(CharSequence str, CharSequence searchStr) { |
| if (str == null || searchStr == null) { |
| return INDEX_NOT_FOUND; |
| } |
| return lastIndexOfIgnoreCase(str, searchStr, str.length()); |
| } |
| |
| /** |
| * <p>Case in-sensitive find of the last index within a CharSequence |
| * from the specified position.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A negative start position returns {@code -1}. |
| * An empty ("") search CharSequence always matches unless the start position is negative. |
| * A start position greater than the string length searches the whole string.</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOfIgnoreCase(null, *, *) = -1 |
| * StringUtils.lastIndexOfIgnoreCase(*, null, *) = -1 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A", 8) = 7 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 8) = 5 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "AB", 8) = 4 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 9) = 5 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", -1) = -1 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A", 0) = 0 |
| * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 0) = -1 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @param startPos the start position |
| * @return the first index of the search CharSequence, |
| * -1 if no match or {@code null} input |
| * @since 2.5 |
| * @since 3.0 Changed signature from lastIndexOfIgnoreCase(String, String, int) to lastIndexOfIgnoreCase(CharSequence, CharSequence, int) |
| */ |
| public static int lastIndexOfIgnoreCase(CharSequence str, CharSequence searchStr, int startPos) { |
| if (str == null || searchStr == null) { |
| return INDEX_NOT_FOUND; |
| } |
| if (startPos > (str.length() - searchStr.length())) { |
| startPos = str.length() - searchStr.length(); |
| } |
| if (startPos < 0) { |
| return INDEX_NOT_FOUND; |
| } |
| if (searchStr.length() == 0) { |
| return startPos; |
| } |
| |
| for (int i = startPos; i >= 0; i--) { |
| if (CharSequenceUtils.regionMatches(str, true, i, searchStr, 0, searchStr.length())) { |
| return i; |
| } |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| // Contains |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if CharSequence contains a search character, handling {@code null}. |
| * This method uses {@link String#indexOf(int)} if possible.</p> |
| * |
| * <p>A {@code null} or empty ("") CharSequence will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.contains(null, *) = false |
| * StringUtils.contains("", *) = false |
| * StringUtils.contains("abc", 'a') = true |
| * StringUtils.contains("abc", 'z') = false |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChar the character to find |
| * @return true if the CharSequence contains the search character, |
| * false if not or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from contains(String, int) to contains(CharSequence, int) |
| */ |
| public static boolean contains(CharSequence seq, int searchChar) { |
| if (isEmpty(seq)) { |
| return false; |
| } |
| return CharSequenceUtils.indexOf(seq, searchChar, 0) >= 0; |
| } |
| |
| /** |
| * <p>Checks if CharSequence contains a search CharSequence, handling {@code null}. |
| * This method uses {@link String#indexOf(String)} if possible.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.contains(null, *) = false |
| * StringUtils.contains(*, null) = false |
| * StringUtils.contains("", "") = true |
| * StringUtils.contains("abc", "") = true |
| * StringUtils.contains("abc", "a") = true |
| * StringUtils.contains("abc", "z") = false |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchSeq the CharSequence to find, may be null |
| * @return true if the CharSequence contains the search CharSequence, |
| * false if not or {@code null} string input |
| * @since 2.0 |
| * @since 3.0 Changed signature from contains(String, String) to contains(CharSequence, CharSequence) |
| */ |
| public static boolean contains(CharSequence seq, CharSequence searchSeq) { |
| if (seq == null || searchSeq == null) { |
| return false; |
| } |
| return CharSequenceUtils.indexOf(seq, searchSeq, 0) >= 0; |
| } |
| |
| /** |
| * <p>Checks if CharSequence contains a search CharSequence irrespective of case, |
| * handling {@code null}. Case-insensitivity is defined as by |
| * {@link String#equalsIgnoreCase(String)}. |
| * |
| * <p>A {@code null} CharSequence will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.contains(null, *) = false |
| * StringUtils.contains(*, null) = false |
| * StringUtils.contains("", "") = true |
| * StringUtils.contains("abc", "") = true |
| * StringUtils.contains("abc", "a") = true |
| * StringUtils.contains("abc", "z") = false |
| * StringUtils.contains("abc", "A") = true |
| * StringUtils.contains("abc", "Z") = false |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStr the CharSequence to find, may be null |
| * @return true if the CharSequence contains the search CharSequence irrespective of |
| * case or false if not or {@code null} string input |
| * @since 3.0 Changed signature from containsIgnoreCase(String, String) to containsIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static boolean containsIgnoreCase(CharSequence str, CharSequence searchStr) { |
| if (str == null || searchStr == null) { |
| return false; |
| } |
| int len = searchStr.length(); |
| int max = str.length() - len; |
| for (int i = 0; i <= max; i++) { |
| if (CharSequenceUtils.regionMatches(str, true, i, searchStr, 0, len)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Check whether the given CharSequence contains any whitespace characters. |
| * @param seq the CharSequence to check (may be {@code null}) |
| * @return {@code true} if the CharSequence is not empty and |
| * contains at least 1 whitespace character |
| * @see java.lang.Character#isWhitespace |
| * @since 3.0 |
| */ |
| // From org.springframework.util.StringUtils, under Apache License 2.0 |
| public static boolean containsWhitespace(CharSequence seq) { |
| if (isEmpty(seq)) { |
| return false; |
| } |
| int strLen = seq.length(); |
| for (int i = 0; i < strLen; i++) { |
| if (Character.isWhitespace(seq.charAt(i))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // IndexOfAny chars |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Search a CharSequence to find the first index of any |
| * character in the given set of characters.</p> |
| * |
| * <p>A {@code null} String will return {@code -1}. |
| * A {@code null} or zero length search array will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfAny(null, *) = -1 |
| * StringUtils.indexOfAny("", *) = -1 |
| * StringUtils.indexOfAny(*, null) = -1 |
| * StringUtils.indexOfAny(*, []) = -1 |
| * StringUtils.indexOfAny("zzabyycdxx",['z','a']) = 0 |
| * StringUtils.indexOfAny("zzabyycdxx",['b','y']) = 3 |
| * StringUtils.indexOfAny("aba", ['z']) = -1 |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param searchChars the chars to search for, may be null |
| * @return the index of any of the chars, -1 if no match or null input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOfAny(String, char[]) to indexOfAny(CharSequence, char...) |
| */ |
| public static int indexOfAny(CharSequence cs, char... searchChars) { |
| if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { |
| return INDEX_NOT_FOUND; |
| } |
| int csLen = cs.length(); |
| int csLast = csLen - 1; |
| int searchLen = searchChars.length; |
| int searchLast = searchLen - 1; |
| for (int i = 0; i < csLen; i++) { |
| char ch = cs.charAt(i); |
| for (int j = 0; j < searchLen; j++) { |
| if (searchChars[j] == ch) { |
| if (i < csLast && j < searchLast && Character.isHighSurrogate(ch)) { |
| // ch is a supplementary character |
| if (searchChars[j + 1] == cs.charAt(i + 1)) { |
| return i; |
| } |
| } else { |
| return i; |
| } |
| } |
| } |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| /** |
| * <p>Search a CharSequence to find the first index of any |
| * character in the given set of characters.</p> |
| * |
| * <p>A {@code null} String will return {@code -1}. |
| * A {@code null} search string will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfAny(null, *) = -1 |
| * StringUtils.indexOfAny("", *) = -1 |
| * StringUtils.indexOfAny(*, null) = -1 |
| * StringUtils.indexOfAny(*, "") = -1 |
| * StringUtils.indexOfAny("zzabyycdxx", "za") = 0 |
| * StringUtils.indexOfAny("zzabyycdxx", "by") = 3 |
| * StringUtils.indexOfAny("aba","z") = -1 |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param searchChars the chars to search for, may be null |
| * @return the index of any of the chars, -1 if no match or null input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOfAny(String, String) to indexOfAny(CharSequence, String) |
| */ |
| public static int indexOfAny(CharSequence cs, String searchChars) { |
| if (isEmpty(cs) || isEmpty(searchChars)) { |
| return INDEX_NOT_FOUND; |
| } |
| return indexOfAny(cs, searchChars.toCharArray()); |
| } |
| |
| // ContainsAny |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if the CharSequence contains any character in the given |
| * set of characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code false}. |
| * A {@code null} or zero length search array will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.containsAny(null, *) = false |
| * StringUtils.containsAny("", *) = false |
| * StringUtils.containsAny(*, null) = false |
| * StringUtils.containsAny(*, []) = false |
| * StringUtils.containsAny("zzabyycdxx",['z','a']) = true |
| * StringUtils.containsAny("zzabyycdxx",['b','y']) = true |
| * StringUtils.containsAny("aba", ['z']) = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param searchChars the chars to search for, may be null |
| * @return the {@code true} if any of the chars are found, |
| * {@code false} if no match or null input |
| * @since 2.4 |
| * @since 3.0 Changed signature from containsAny(String, char[]) to containsAny(CharSequence, char...) |
| */ |
| public static boolean containsAny(CharSequence cs, char... searchChars) { |
| if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { |
| return false; |
| } |
| int csLength = cs.length(); |
| int searchLength = searchChars.length; |
| int csLast = csLength - 1; |
| int searchLast = searchLength - 1; |
| for (int i = 0; i < csLength; i++) { |
| char ch = cs.charAt(i); |
| for (int j = 0; j < searchLength; j++) { |
| if (searchChars[j] == ch) { |
| if (Character.isHighSurrogate(ch)) { |
| if (j == searchLast) { |
| // missing low surrogate, fine, like String.indexOf(String) |
| return true; |
| } |
| if (i < csLast && searchChars[j + 1] == cs.charAt(i + 1)) { |
| return true; |
| } |
| } else { |
| // ch is in the Basic Multilingual Plane |
| return true; |
| } |
| } |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * <p> |
| * Checks if the CharSequence contains any character in the given set of characters. |
| * </p> |
| * |
| * <p> |
| * A {@code null} CharSequence will return {@code false}. A {@code null} search CharSequence will return |
| * {@code false}. |
| * </p> |
| * |
| * <pre> |
| * StringUtils.containsAny(null, *) = false |
| * StringUtils.containsAny("", *) = false |
| * StringUtils.containsAny(*, null) = false |
| * StringUtils.containsAny(*, "") = false |
| * StringUtils.containsAny("zzabyycdxx", "za") = true |
| * StringUtils.containsAny("zzabyycdxx", "by") = true |
| * StringUtils.containsAny("aba","z") = false |
| * </pre> |
| * |
| * @param cs |
| * the CharSequence to check, may be null |
| * @param searchChars |
| * the chars to search for, may be null |
| * @return the {@code true} if any of the chars are found, {@code false} if no match or null input |
| * @since 2.4 |
| * @since 3.0 Changed signature from containsAny(String, String) to containsAny(CharSequence, CharSequence) |
| */ |
| public static boolean containsAny(CharSequence cs, CharSequence searchChars) { |
| if (searchChars == null) { |
| return false; |
| } |
| return containsAny(cs, CharSequenceUtils.toCharArray(searchChars)); |
| } |
| |
| // IndexOfAnyBut chars |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Searches a CharSequence to find the first index of any |
| * character not in the given set of characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A {@code null} or zero length search array will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfAnyBut(null, *) = -1 |
| * StringUtils.indexOfAnyBut("", *) = -1 |
| * StringUtils.indexOfAnyBut(*, null) = -1 |
| * StringUtils.indexOfAnyBut(*, []) = -1 |
| * StringUtils.indexOfAnyBut("zzabyycdxx", new char[] {'z', 'a'} ) = 3 |
| * StringUtils.indexOfAnyBut("aba", new char[] {'z'} ) = 0 |
| * StringUtils.indexOfAnyBut("aba", new char[] {'a', 'b'} ) = -1 |
| |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param searchChars the chars to search for, may be null |
| * @return the index of any of the chars, -1 if no match or null input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOfAnyBut(String, char[]) to indexOfAnyBut(CharSequence, char...) |
| */ |
| public static int indexOfAnyBut(CharSequence cs, char... searchChars) { |
| if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { |
| return INDEX_NOT_FOUND; |
| } |
| int csLen = cs.length(); |
| int csLast = csLen - 1; |
| int searchLen = searchChars.length; |
| int searchLast = searchLen - 1; |
| outer: |
| for (int i = 0; i < csLen; i++) { |
| char ch = cs.charAt(i); |
| for (int j = 0; j < searchLen; j++) { |
| if (searchChars[j] == ch) { |
| if (i < csLast && j < searchLast && Character.isHighSurrogate(ch)) { |
| if (searchChars[j + 1] == cs.charAt(i + 1)) { |
| continue outer; |
| } |
| } else { |
| continue outer; |
| } |
| } |
| } |
| return i; |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| /** |
| * <p>Search a CharSequence to find the first index of any |
| * character not in the given set of characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A {@code null} or empty search string will return {@code -1}.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfAnyBut(null, *) = -1 |
| * StringUtils.indexOfAnyBut("", *) = -1 |
| * StringUtils.indexOfAnyBut(*, null) = -1 |
| * StringUtils.indexOfAnyBut(*, "") = -1 |
| * StringUtils.indexOfAnyBut("zzabyycdxx", "za") = 3 |
| * StringUtils.indexOfAnyBut("zzabyycdxx", "") = -1 |
| * StringUtils.indexOfAnyBut("aba","ab") = -1 |
| * </pre> |
| * |
| * @param seq the CharSequence to check, may be null |
| * @param searchChars the chars to search for, may be null |
| * @return the index of any of the chars, -1 if no match or null input |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOfAnyBut(String, String) to indexOfAnyBut(CharSequence, CharSequence) |
| */ |
| public static int indexOfAnyBut(CharSequence seq, CharSequence searchChars) { |
| if (isEmpty(seq) || isEmpty(searchChars)) { |
| return INDEX_NOT_FOUND; |
| } |
| int strLen = seq.length(); |
| for (int i = 0; i < strLen; i++) { |
| char ch = seq.charAt(i); |
| boolean chFound = CharSequenceUtils.indexOf(searchChars, ch, 0) >= 0; |
| if (i + 1 < strLen && Character.isHighSurrogate(ch)) { |
| char ch2 = seq.charAt(i + 1); |
| if (chFound && CharSequenceUtils.indexOf(searchChars, ch2, 0) < 0) { |
| return i; |
| } |
| } else { |
| if (!chFound) { |
| return i; |
| } |
| } |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| // ContainsOnly |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if the CharSequence contains only certain characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code false}. |
| * A {@code null} valid character array will return {@code false}. |
| * An empty CharSequence (length()=0) always returns {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.containsOnly(null, *) = false |
| * StringUtils.containsOnly(*, null) = false |
| * StringUtils.containsOnly("", *) = true |
| * StringUtils.containsOnly("ab", '') = false |
| * StringUtils.containsOnly("abab", 'abc') = true |
| * StringUtils.containsOnly("ab1", 'abc') = false |
| * StringUtils.containsOnly("abz", 'abc') = false |
| * </pre> |
| * |
| * @param cs the String to check, may be null |
| * @param valid an array of valid chars, may be null |
| * @return true if it only contains valid chars and is non-null |
| * @since 3.0 Changed signature from containsOnly(String, char[]) to containsOnly(CharSequence, char...) |
| */ |
| public static boolean containsOnly(CharSequence cs, char... valid) { |
| // All these pre-checks are to maintain API with an older version |
| if (valid == null || cs == null) { |
| return false; |
| } |
| if (cs.length() == 0) { |
| return true; |
| } |
| if (valid.length == 0) { |
| return false; |
| } |
| return indexOfAnyBut(cs, valid) == INDEX_NOT_FOUND; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only certain characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code false}. |
| * A {@code null} valid character String will return {@code false}. |
| * An empty String (length()=0) always returns {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.containsOnly(null, *) = false |
| * StringUtils.containsOnly(*, null) = false |
| * StringUtils.containsOnly("", *) = true |
| * StringUtils.containsOnly("ab", "") = false |
| * StringUtils.containsOnly("abab", "abc") = true |
| * StringUtils.containsOnly("ab1", "abc") = false |
| * StringUtils.containsOnly("abz", "abc") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param validChars a String of valid chars, may be null |
| * @return true if it only contains valid chars and is non-null |
| * @since 2.0 |
| * @since 3.0 Changed signature from containsOnly(String, String) to containsOnly(CharSequence, String) |
| */ |
| public static boolean containsOnly(CharSequence cs, String validChars) { |
| if (cs == null || validChars == null) { |
| return false; |
| } |
| return containsOnly(cs, validChars.toCharArray()); |
| } |
| |
| // ContainsNone |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks that the CharSequence does not contain certain characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code true}. |
| * A {@code null} invalid character array will return {@code true}. |
| * An empty CharSequence (length()=0) always returns true.</p> |
| * |
| * <pre> |
| * StringUtils.containsNone(null, *) = true |
| * StringUtils.containsNone(*, null) = true |
| * StringUtils.containsNone("", *) = true |
| * StringUtils.containsNone("ab", '') = true |
| * StringUtils.containsNone("abab", 'xyz') = true |
| * StringUtils.containsNone("ab1", 'xyz') = true |
| * StringUtils.containsNone("abz", 'xyz') = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param searchChars an array of invalid chars, may be null |
| * @return true if it contains none of the invalid chars, or is null |
| * @since 2.0 |
| * @since 3.0 Changed signature from containsNone(String, char[]) to containsNone(CharSequence, char...) |
| */ |
| public static boolean containsNone(CharSequence cs, char... searchChars) { |
| if (cs == null || searchChars == null) { |
| return true; |
| } |
| int csLen = cs.length(); |
| int csLast = csLen - 1; |
| int searchLen = searchChars.length; |
| int searchLast = searchLen - 1; |
| for (int i = 0; i < csLen; i++) { |
| char ch = cs.charAt(i); |
| for (int j = 0; j < searchLen; j++) { |
| if (searchChars[j] == ch) { |
| if (Character.isHighSurrogate(ch)) { |
| if (j == searchLast) { |
| // missing low surrogate, fine, like String.indexOf(String) |
| return false; |
| } |
| if (i < csLast && searchChars[j + 1] == cs.charAt(i + 1)) { |
| return false; |
| } |
| } else { |
| // ch is in the Basic Multilingual Plane |
| return false; |
| } |
| } |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks that the CharSequence does not contain certain characters.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code true}. |
| * A {@code null} invalid character array will return {@code true}. |
| * An empty String ("") always returns true.</p> |
| * |
| * <pre> |
| * StringUtils.containsNone(null, *) = true |
| * StringUtils.containsNone(*, null) = true |
| * StringUtils.containsNone("", *) = true |
| * StringUtils.containsNone("ab", "") = true |
| * StringUtils.containsNone("abab", "xyz") = true |
| * StringUtils.containsNone("ab1", "xyz") = true |
| * StringUtils.containsNone("abz", "xyz") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @param invalidChars a String of invalid chars, may be null |
| * @return true if it contains none of the invalid chars, or is null |
| * @since 2.0 |
| * @since 3.0 Changed signature from containsNone(String, String) to containsNone(CharSequence, String) |
| */ |
| public static boolean containsNone(CharSequence cs, String invalidChars) { |
| if (cs == null || invalidChars == null) { |
| return true; |
| } |
| return containsNone(cs, invalidChars.toCharArray()); |
| } |
| |
| // IndexOfAny strings |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Find the first index of any of a set of potential substrings.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A {@code null} or zero length search array will return {@code -1}. |
| * A {@code null} search array entry will be ignored, but a search |
| * array containing "" will return {@code 0} if {@code str} is not |
| * null. This method uses {@link String#indexOf(String)} if possible.</p> |
| * |
| * <pre> |
| * StringUtils.indexOfAny(null, *) = -1 |
| * StringUtils.indexOfAny(*, null) = -1 |
| * StringUtils.indexOfAny(*, []) = -1 |
| * StringUtils.indexOfAny("zzabyycdxx", ["ab","cd"]) = 2 |
| * StringUtils.indexOfAny("zzabyycdxx", ["cd","ab"]) = 2 |
| * StringUtils.indexOfAny("zzabyycdxx", ["mn","op"]) = -1 |
| * StringUtils.indexOfAny("zzabyycdxx", ["zab","aby"]) = 1 |
| * StringUtils.indexOfAny("zzabyycdxx", [""]) = 0 |
| * StringUtils.indexOfAny("", [""]) = 0 |
| * StringUtils.indexOfAny("", ["a"]) = -1 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStrs the CharSequences to search for, may be null |
| * @return the first index of any of the searchStrs in str, -1 if no match |
| * @since 3.0 Changed signature from indexOfAny(String, String[]) to indexOfAny(CharSequence, CharSequence...) |
| */ |
| public static int indexOfAny(CharSequence str, CharSequence... searchStrs) { |
| if (str == null || searchStrs == null) { |
| return INDEX_NOT_FOUND; |
| } |
| int sz = searchStrs.length; |
| |
| // String's can't have a MAX_VALUEth index. |
| int ret = Integer.MAX_VALUE; |
| |
| int tmp = 0; |
| for (int i = 0; i < sz; i++) { |
| CharSequence search = searchStrs[i]; |
| if (search == null) { |
| continue; |
| } |
| tmp = CharSequenceUtils.indexOf(str, search, 0); |
| if (tmp == INDEX_NOT_FOUND) { |
| continue; |
| } |
| |
| if (tmp < ret) { |
| ret = tmp; |
| } |
| } |
| |
| return (ret == Integer.MAX_VALUE) ? INDEX_NOT_FOUND : ret; |
| } |
| |
| /** |
| * <p>Find the latest index of any of a set of potential substrings.</p> |
| * |
| * <p>A {@code null} CharSequence will return {@code -1}. |
| * A {@code null} search array will return {@code -1}. |
| * A {@code null} or zero length search array entry will be ignored, |
| * but a search array containing "" will return the length of {@code str} |
| * if {@code str} is not null. This method uses {@link String#indexOf(String)} if possible</p> |
| * |
| * <pre> |
| * StringUtils.lastIndexOfAny(null, *) = -1 |
| * StringUtils.lastIndexOfAny(*, null) = -1 |
| * StringUtils.lastIndexOfAny(*, []) = -1 |
| * StringUtils.lastIndexOfAny(*, [null]) = -1 |
| * StringUtils.lastIndexOfAny("zzabyycdxx", ["ab","cd"]) = 6 |
| * StringUtils.lastIndexOfAny("zzabyycdxx", ["cd","ab"]) = 6 |
| * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn","op"]) = -1 |
| * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn","op"]) = -1 |
| * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn",""]) = 10 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param searchStrs the CharSequences to search for, may be null |
| * @return the last index of any of the CharSequences, -1 if no match |
| * @since 3.0 Changed signature from lastIndexOfAny(String, String[]) to lastIndexOfAny(CharSequence, CharSequence) |
| */ |
| public static int lastIndexOfAny(CharSequence str, CharSequence... searchStrs) { |
| if (str == null || searchStrs == null) { |
| return INDEX_NOT_FOUND; |
| } |
| int sz = searchStrs.length; |
| int ret = INDEX_NOT_FOUND; |
| int tmp = 0; |
| for (int i = 0; i < sz; i++) { |
| CharSequence search = searchStrs[i]; |
| if (search == null) { |
| continue; |
| } |
| tmp = CharSequenceUtils.lastIndexOf(str, search, str.length()); |
| if (tmp > ret) { |
| ret = tmp; |
| } |
| } |
| return ret; |
| } |
| |
| // Substring |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Gets a substring from the specified String avoiding exceptions.</p> |
| * |
| * <p>A negative start position can be used to start {@code n} |
| * characters from the end of the String.</p> |
| * |
| * <p>A {@code null} String will return {@code null}. |
| * An empty ("") String will return "".</p> |
| * |
| * <pre> |
| * StringUtils.substring(null, *) = null |
| * StringUtils.substring("", *) = "" |
| * StringUtils.substring("abc", 0) = "abc" |
| * StringUtils.substring("abc", 2) = "c" |
| * StringUtils.substring("abc", 4) = "" |
| * StringUtils.substring("abc", -2) = "bc" |
| * StringUtils.substring("abc", -4) = "abc" |
| * </pre> |
| * |
| * @param str the String to get the substring from, may be null |
| * @param start the position to start from, negative means |
| * count back from the end of the String by this many characters |
| * @return substring from start position, {@code null} if null String input |
| */ |
| public static String substring(String str, int start) { |
| if (str == null) { |
| return null; |
| } |
| |
| // handle negatives, which means last n characters |
| if (start < 0) { |
| start = str.length() + start; // remember start is negative |
| } |
| |
| if (start < 0) { |
| start = 0; |
| } |
| if (start > str.length()) { |
| return EMPTY; |
| } |
| |
| return str.substring(start); |
| } |
| |
| /** |
| * <p>Gets a substring from the specified String avoiding exceptions.</p> |
| * |
| * <p>A negative start position can be used to start/end {@code n} |
| * characters from the end of the String.</p> |
| * |
| * <p>The returned substring starts with the character in the {@code start} |
| * position and ends before the {@code end} position. All position counting is |
| * zero-based -- i.e., to start at the beginning of the string use |
| * {@code start = 0}. Negative start and end positions can be used to |
| * specify offsets relative to the end of the String.</p> |
| * |
| * <p>If {@code start} is not strictly to the left of {@code end}, "" |
| * is returned.</p> |
| * |
| * <pre> |
| * StringUtils.substring(null, *, *) = null |
| * StringUtils.substring("", * , *) = ""; |
| * StringUtils.substring("abc", 0, 2) = "ab" |
| * StringUtils.substring("abc", 2, 0) = "" |
| * StringUtils.substring("abc", 2, 4) = "c" |
| * StringUtils.substring("abc", 4, 6) = "" |
| * StringUtils.substring("abc", 2, 2) = "" |
| * StringUtils.substring("abc", -2, -1) = "b" |
| * StringUtils.substring("abc", -4, 2) = "ab" |
| * </pre> |
| * |
| * @param str the String to get the substring from, may be null |
| * @param start the position to start from, negative means |
| * count back from the end of the String by this many characters |
| * @param end the position to end at (exclusive), negative means |
| * count back from the end of the String by this many characters |
| * @return substring from start position to end position, |
| * {@code null} if null String input |
| */ |
| public static String substring(String str, int start, int end) { |
| if (str == null) { |
| return null; |
| } |
| |
| // handle negatives |
| if (end < 0) { |
| end = str.length() + end; // remember end is negative |
| } |
| if (start < 0) { |
| start = str.length() + start; // remember start is negative |
| } |
| |
| // check length next |
| if (end > str.length()) { |
| end = str.length(); |
| } |
| |
| // if start is greater than end, return "" |
| if (start > end) { |
| return EMPTY; |
| } |
| |
| if (start < 0) { |
| start = 0; |
| } |
| if (end < 0) { |
| end = 0; |
| } |
| |
| return str.substring(start, end); |
| } |
| |
| // Left/Right/Mid |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Gets the leftmost {@code len} characters of a String.</p> |
| * |
| * <p>If {@code len} characters are not available, or the |
| * String is {@code null}, the String will be returned without |
| * an exception. An empty String is returned if len is negative.</p> |
| * |
| * <pre> |
| * StringUtils.left(null, *) = null |
| * StringUtils.left(*, -ve) = "" |
| * StringUtils.left("", *) = "" |
| * StringUtils.left("abc", 0) = "" |
| * StringUtils.left("abc", 2) = "ab" |
| * StringUtils.left("abc", 4) = "abc" |
| * </pre> |
| * |
| * @param str the String to get the leftmost characters from, may be null |
| * @param len the length of the required String |
| * @return the leftmost characters, {@code null} if null String input |
| */ |
| public static String left(String str, int len) { |
| if (str == null) { |
| return null; |
| } |
| if (len < 0) { |
| return EMPTY; |
| } |
| if (str.length() <= len) { |
| return str; |
| } |
| return str.substring(0, len); |
| } |
| |
| /** |
| * <p>Gets the rightmost {@code len} characters of a String.</p> |
| * |
| * <p>If {@code len} characters are not available, or the String |
| * is {@code null}, the String will be returned without an |
| * an exception. An empty String is returned if len is negative.</p> |
| * |
| * <pre> |
| * StringUtils.right(null, *) = null |
| * StringUtils.right(*, -ve) = "" |
| * StringUtils.right("", *) = "" |
| * StringUtils.right("abc", 0) = "" |
| * StringUtils.right("abc", 2) = "bc" |
| * StringUtils.right("abc", 4) = "abc" |
| * </pre> |
| * |
| * @param str the String to get the rightmost characters from, may be null |
| * @param len the length of the required String |
| * @return the rightmost characters, {@code null} if null String input |
| */ |
| public static String right(String str, int len) { |
| if (str == null) { |
| return null; |
| } |
| if (len < 0) { |
| return EMPTY; |
| } |
| if (str.length() <= len) { |
| return str; |
| } |
| return str.substring(str.length() - len); |
| } |
| |
| /** |
| * <p>Gets {@code len} characters from the middle of a String.</p> |
| * |
| * <p>If {@code len} characters are not available, the remainder |
| * of the String will be returned without an exception. If the |
| * String is {@code null}, {@code null} will be returned. |
| * An empty String is returned if len is negative or exceeds the |
| * length of {@code str}.</p> |
| * |
| * <pre> |
| * StringUtils.mid(null, *, *) = null |
| * StringUtils.mid(*, *, -ve) = "" |
| * StringUtils.mid("", 0, *) = "" |
| * StringUtils.mid("abc", 0, 2) = "ab" |
| * StringUtils.mid("abc", 0, 4) = "abc" |
| * StringUtils.mid("abc", 2, 4) = "c" |
| * StringUtils.mid("abc", 4, 2) = "" |
| * StringUtils.mid("abc", -2, 2) = "ab" |
| * </pre> |
| * |
| * @param str the String to get the characters from, may be null |
| * @param pos the position to start from, negative treated as zero |
| * @param len the length of the required String |
| * @return the middle characters, {@code null} if null String input |
| */ |
| public static String mid(String str, int pos, int len) { |
| if (str == null) { |
| return null; |
| } |
| if (len < 0 || pos > str.length()) { |
| return EMPTY; |
| } |
| if (pos < 0) { |
| pos = 0; |
| } |
| if (str.length() <= (pos + len)) { |
| return str.substring(pos); |
| } |
| return str.substring(pos, pos + len); |
| } |
| |
| // SubStringAfter/SubStringBefore |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Gets the substring before the first occurrence of a separator. |
| * The separator is not returned.</p> |
| * |
| * <p>A {@code null} string input will return {@code null}. |
| * An empty ("") string input will return the empty string. |
| * A {@code null} separator will return the input string.</p> |
| * |
| * <p>If nothing is found, the string input is returned.</p> |
| * |
| * <pre> |
| * StringUtils.substringBefore(null, *) = null |
| * StringUtils.substringBefore("", *) = "" |
| * StringUtils.substringBefore("abc", "a") = "" |
| * StringUtils.substringBefore("abcba", "b") = "a" |
| * StringUtils.substringBefore("abc", "c") = "ab" |
| * StringUtils.substringBefore("abc", "d") = "abc" |
| * StringUtils.substringBefore("abc", "") = "" |
| * StringUtils.substringBefore("abc", null) = "abc" |
| * </pre> |
| * |
| * @param str the String to get a substring from, may be null |
| * @param separator the String to search for, may be null |
| * @return the substring before the first occurrence of the separator, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String substringBefore(String str, String separator) { |
| if (isEmpty(str) || separator == null) { |
| return str; |
| } |
| if (separator.length() == 0) { |
| return EMPTY; |
| } |
| int pos = str.indexOf(separator); |
| if (pos == INDEX_NOT_FOUND) { |
| return str; |
| } |
| return str.substring(0, pos); |
| } |
| |
| /** |
| * <p>Gets the substring after the first occurrence of a separator. |
| * The separator is not returned.</p> |
| * |
| * <p>A {@code null} string input will return {@code null}. |
| * An empty ("") string input will return the empty string. |
| * A {@code null} separator will return the empty string if the |
| * input string is not {@code null}.</p> |
| * |
| * <p>If nothing is found, the empty string is returned.</p> |
| * |
| * <pre> |
| * StringUtils.substringAfter(null, *) = null |
| * StringUtils.substringAfter("", *) = "" |
| * StringUtils.substringAfter(*, null) = "" |
| * StringUtils.substringAfter("abc", "a") = "bc" |
| * StringUtils.substringAfter("abcba", "b") = "cba" |
| * StringUtils.substringAfter("abc", "c") = "" |
| * StringUtils.substringAfter("abc", "d") = "" |
| * StringUtils.substringAfter("abc", "") = "abc" |
| * </pre> |
| * |
| * @param str the String to get a substring from, may be null |
| * @param separator the String to search for, may be null |
| * @return the substring after the first occurrence of the separator, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String substringAfter(String str, String separator) { |
| if (isEmpty(str)) { |
| return str; |
| } |
| if (separator == null) { |
| return EMPTY; |
| } |
| int pos = str.indexOf(separator); |
| if (pos == INDEX_NOT_FOUND) { |
| return EMPTY; |
| } |
| return str.substring(pos + separator.length()); |
| } |
| |
| /** |
| * <p>Gets the substring before the last occurrence of a separator. |
| * The separator is not returned.</p> |
| * |
| * <p>A {@code null} string input will return {@code null}. |
| * An empty ("") string input will return the empty string. |
| * An empty or {@code null} separator will return the input string.</p> |
| * |
| * <p>If nothing is found, the string input is returned.</p> |
| * |
| * <pre> |
| * StringUtils.substringBeforeLast(null, *) = null |
| * StringUtils.substringBeforeLast("", *) = "" |
| * StringUtils.substringBeforeLast("abcba", "b") = "abc" |
| * StringUtils.substringBeforeLast("abc", "c") = "ab" |
| * StringUtils.substringBeforeLast("a", "a") = "" |
| * StringUtils.substringBeforeLast("a", "z") = "a" |
| * StringUtils.substringBeforeLast("a", null) = "a" |
| * StringUtils.substringBeforeLast("a", "") = "a" |
| * </pre> |
| * |
| * @param str the String to get a substring from, may be null |
| * @param separator the String to search for, may be null |
| * @return the substring before the last occurrence of the separator, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String substringBeforeLast(String str, String separator) { |
| if (isEmpty(str) || isEmpty(separator)) { |
| return str; |
| } |
| int pos = str.lastIndexOf(separator); |
| if (pos == INDEX_NOT_FOUND) { |
| return str; |
| } |
| return str.substring(0, pos); |
| } |
| |
| /** |
| * <p>Gets the substring after the last occurrence of a separator. |
| * The separator is not returned.</p> |
| * |
| * <p>A {@code null} string input will return {@code null}. |
| * An empty ("") string input will return the empty string. |
| * An empty or {@code null} separator will return the empty string if |
| * the input string is not {@code null}.</p> |
| * |
| * <p>If nothing is found, the empty string is returned.</p> |
| * |
| * <pre> |
| * StringUtils.substringAfterLast(null, *) = null |
| * StringUtils.substringAfterLast("", *) = "" |
| * StringUtils.substringAfterLast(*, "") = "" |
| * StringUtils.substringAfterLast(*, null) = "" |
| * StringUtils.substringAfterLast("abc", "a") = "bc" |
| * StringUtils.substringAfterLast("abcba", "b") = "a" |
| * StringUtils.substringAfterLast("abc", "c") = "" |
| * StringUtils.substringAfterLast("a", "a") = "" |
| * StringUtils.substringAfterLast("a", "z") = "" |
| * </pre> |
| * |
| * @param str the String to get a substring from, may be null |
| * @param separator the String to search for, may be null |
| * @return the substring after the last occurrence of the separator, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String substringAfterLast(String str, String separator) { |
| if (isEmpty(str)) { |
| return str; |
| } |
| if (isEmpty(separator)) { |
| return EMPTY; |
| } |
| int pos = str.lastIndexOf(separator); |
| if (pos == INDEX_NOT_FOUND || pos == (str.length() - separator.length())) { |
| return EMPTY; |
| } |
| return str.substring(pos + separator.length()); |
| } |
| |
| // Substring between |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Gets the String that is nested in between two instances of the |
| * same String.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} tag returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.substringBetween(null, *) = null |
| * StringUtils.substringBetween("", "") = "" |
| * StringUtils.substringBetween("", "tag") = null |
| * StringUtils.substringBetween("tagabctag", null) = null |
| * StringUtils.substringBetween("tagabctag", "") = "" |
| * StringUtils.substringBetween("tagabctag", "tag") = "abc" |
| * </pre> |
| * |
| * @param str the String containing the substring, may be null |
| * @param tag the String before and after the substring, may be null |
| * @return the substring, {@code null} if no match |
| * @since 2.0 |
| */ |
| public static String substringBetween(String str, String tag) { |
| return substringBetween(str, tag, tag); |
| } |
| |
| /** |
| * <p>Gets the String that is nested in between two Strings. |
| * Only the first match is returned.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} open/close returns {@code null} (no match). |
| * An empty ("") open and close returns an empty string.</p> |
| * |
| * <pre> |
| * StringUtils.substringBetween("wx[b]yz", "[", "]") = "b" |
| * StringUtils.substringBetween(null, *, *) = null |
| * StringUtils.substringBetween(*, null, *) = null |
| * StringUtils.substringBetween(*, *, null) = null |
| * StringUtils.substringBetween("", "", "") = "" |
| * StringUtils.substringBetween("", "", "]") = null |
| * StringUtils.substringBetween("", "[", "]") = null |
| * StringUtils.substringBetween("yabcz", "", "") = "" |
| * StringUtils.substringBetween("yabcz", "y", "z") = "abc" |
| * StringUtils.substringBetween("yabczyabcz", "y", "z") = "abc" |
| * </pre> |
| * |
| * @param str the String containing the substring, may be null |
| * @param open the String before the substring, may be null |
| * @param close the String after the substring, may be null |
| * @return the substring, {@code null} if no match |
| * @since 2.0 |
| */ |
| public static String substringBetween(String str, String open, String close) { |
| if (str == null || open == null || close == null) { |
| return null; |
| } |
| int start = str.indexOf(open); |
| if (start != INDEX_NOT_FOUND) { |
| int end = str.indexOf(close, start + open.length()); |
| if (end != INDEX_NOT_FOUND) { |
| return str.substring(start + open.length(), end); |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * <p>Searches a String for substrings delimited by a start and end tag, |
| * returning all matching substrings in an array.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} open/close returns {@code null} (no match). |
| * An empty ("") open/close returns {@code null} (no match).</p> |
| * |
| * <pre> |
| * StringUtils.substringsBetween("[a][b][c]", "[", "]") = ["a","b","c"] |
| * StringUtils.substringsBetween(null, *, *) = null |
| * StringUtils.substringsBetween(*, null, *) = null |
| * StringUtils.substringsBetween(*, *, null) = null |
| * StringUtils.substringsBetween("", "[", "]") = [] |
| * </pre> |
| * |
| * @param str the String containing the substrings, null returns null, empty returns empty |
| * @param open the String identifying the start of the substring, empty returns null |
| * @param close the String identifying the end of the substring, empty returns null |
| * @return a String Array of substrings, or {@code null} if no match |
| * @since 2.3 |
| */ |
| public static String[] substringsBetween(String str, String open, String close) { |
| if (str == null || isEmpty(open) || isEmpty(close)) { |
| return null; |
| } |
| int strLen = str.length(); |
| if (strLen == 0) { |
| return ArrayUtils.EMPTY_STRING_ARRAY; |
| } |
| int closeLen = close.length(); |
| int openLen = open.length(); |
| List<String> list = new ArrayList<String>(); |
| int pos = 0; |
| while (pos < (strLen - closeLen)) { |
| int start = str.indexOf(open, pos); |
| if (start < 0) { |
| break; |
| } |
| start += openLen; |
| int end = str.indexOf(close, start); |
| if (end < 0) { |
| break; |
| } |
| list.add(str.substring(start, end)); |
| pos = end + closeLen; |
| } |
| if (list.isEmpty()) { |
| return null; |
| } |
| return list.toArray(new String [list.size()]); |
| } |
| |
| // Nested extraction |
| //----------------------------------------------------------------------- |
| |
| // Splitting |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Splits the provided text into an array, using whitespace as the |
| * separator. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as one separator. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.split(null) = null |
| * StringUtils.split("") = [] |
| * StringUtils.split("abc def") = ["abc", "def"] |
| * StringUtils.split("abc def") = ["abc", "def"] |
| * StringUtils.split(" abc ") = ["abc"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @return an array of parsed Strings, {@code null} if null String input |
| */ |
| public static String[] split(String str) { |
| return split(str, null, -1); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator specified. |
| * This is an alternative to using StringTokenizer.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as one separator. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.split(null, *) = null |
| * StringUtils.split("", *) = [] |
| * StringUtils.split("a.b.c", '.') = ["a", "b", "c"] |
| * StringUtils.split("a..b.c", '.') = ["a", "b", "c"] |
| * StringUtils.split("a:b:c", '.') = ["a:b:c"] |
| * StringUtils.split("a b c", ' ') = ["a", "b", "c"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separatorChar the character used as the delimiter |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String[] split(String str, char separatorChar) { |
| return splitWorker(str, separatorChar, false); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separators specified. |
| * This is an alternative to using StringTokenizer.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as one separator. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separatorChars splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.split(null, *) = null |
| * StringUtils.split("", *) = [] |
| * StringUtils.split("abc def", null) = ["abc", "def"] |
| * StringUtils.split("abc def", " ") = ["abc", "def"] |
| * StringUtils.split("abc def", " ") = ["abc", "def"] |
| * StringUtils.split("ab:cd:ef", ":") = ["ab", "cd", "ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separatorChars the characters used as the delimiters, |
| * {@code null} splits on whitespace |
| * @return an array of parsed Strings, {@code null} if null String input |
| */ |
| public static String[] split(String str, String separatorChars) { |
| return splitWorker(str, separatorChars, -1, false); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array with a maximum length, |
| * separators specified.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as one separator.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separatorChars splits on whitespace.</p> |
| * |
| * <p>If more than {@code max} delimited substrings are found, the last |
| * returned string includes all characters after the first {@code max - 1} |
| * returned strings (including separator characters).</p> |
| * |
| * <pre> |
| * StringUtils.split(null, *, *) = null |
| * StringUtils.split("", *, *) = [] |
| * StringUtils.split("ab de fg", null, 0) = ["ab", "cd", "ef"] |
| * StringUtils.split("ab de fg", null, 0) = ["ab", "cd", "ef"] |
| * StringUtils.split("ab:cd:ef", ":", 0) = ["ab", "cd", "ef"] |
| * StringUtils.split("ab:cd:ef", ":", 2) = ["ab", "cd:ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separatorChars the characters used as the delimiters, |
| * {@code null} splits on whitespace |
| * @param max the maximum number of elements to include in the |
| * array. A zero or negative value implies no limit |
| * @return an array of parsed Strings, {@code null} if null String input |
| */ |
| public static String[] split(String str, String separatorChars, int max) { |
| return splitWorker(str, separatorChars, max, false); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator string specified.</p> |
| * |
| * <p>The separator(s) will not be included in the returned String array. |
| * Adjacent separators are treated as one separator.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separator splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.splitByWholeSeparator(null, *) = null |
| * StringUtils.splitByWholeSeparator("", *) = [] |
| * StringUtils.splitByWholeSeparator("ab de fg", null) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparator("ab de fg", null) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparator("ab:cd:ef", ":") = ["ab", "cd", "ef"] |
| * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-") = ["ab", "cd", "ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separator String containing the String to be used as a delimiter, |
| * {@code null} splits on whitespace |
| * @return an array of parsed Strings, {@code null} if null String was input |
| */ |
| public static String[] splitByWholeSeparator(String str, String separator) { |
| return splitByWholeSeparatorWorker( str, separator, -1, false ) ; |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator string specified. |
| * Returns a maximum of {@code max} substrings.</p> |
| * |
| * <p>The separator(s) will not be included in the returned String array. |
| * Adjacent separators are treated as one separator.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separator splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.splitByWholeSeparator(null, *, *) = null |
| * StringUtils.splitByWholeSeparator("", *, *) = [] |
| * StringUtils.splitByWholeSeparator("ab de fg", null, 0) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparator("ab de fg", null, 0) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparator("ab:cd:ef", ":", 2) = ["ab", "cd:ef"] |
| * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-", 5) = ["ab", "cd", "ef"] |
| * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-", 2) = ["ab", "cd-!-ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separator String containing the String to be used as a delimiter, |
| * {@code null} splits on whitespace |
| * @param max the maximum number of elements to include in the returned |
| * array. A zero or negative value implies no limit. |
| * @return an array of parsed Strings, {@code null} if null String was input |
| */ |
| public static String[] splitByWholeSeparator( String str, String separator, int max ) { |
| return splitByWholeSeparatorWorker(str, separator, max, false); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator string specified. </p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separator splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens(null, *) = null |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("", *) = [] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null) = ["ab", "", "", "de", "fg"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab:cd:ef", ":") = ["ab", "cd", "ef"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-") = ["ab", "cd", "ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separator String containing the String to be used as a delimiter, |
| * {@code null} splits on whitespace |
| * @return an array of parsed Strings, {@code null} if null String was input |
| * @since 2.4 |
| */ |
| public static String[] splitByWholeSeparatorPreserveAllTokens(String str, String separator) { |
| return splitByWholeSeparatorWorker(str, separator, -1, true); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator string specified. |
| * Returns a maximum of {@code max} substrings.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separator splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens(null, *, *) = null |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("", *, *) = [] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null, 0) = ["ab", "de", "fg"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null, 0) = ["ab", "", "", "de", "fg"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab:cd:ef", ":", 2) = ["ab", "cd:ef"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-", 5) = ["ab", "cd", "ef"] |
| * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-", 2) = ["ab", "cd-!-ef"] |
| * </pre> |
| * |
| * @param str the String to parse, may be null |
| * @param separator String containing the String to be used as a delimiter, |
| * {@code null} splits on whitespace |
| * @param max the maximum number of elements to include in the returned |
| * array. A zero or negative value implies no limit. |
| * @return an array of parsed Strings, {@code null} if null String was input |
| * @since 2.4 |
| */ |
| public static String[] splitByWholeSeparatorPreserveAllTokens(String str, String separator, int max) { |
| return splitByWholeSeparatorWorker(str, separator, max, true); |
| } |
| |
| /** |
| * Performs the logic for the {@code splitByWholeSeparatorPreserveAllTokens} methods. |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separator String containing the String to be used as a delimiter, |
| * {@code null} splits on whitespace |
| * @param max the maximum number of elements to include in the returned |
| * array. A zero or negative value implies no limit. |
| * @param preserveAllTokens if {@code true}, adjacent separators are |
| * treated as empty token separators; if {@code false}, adjacent |
| * separators are treated as one separator. |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.4 |
| */ |
| private static String[] splitByWholeSeparatorWorker( |
| String str, String separator, int max, boolean preserveAllTokens) { |
| if (str == null) { |
| return null; |
| } |
| |
| int len = str.length(); |
| |
| if (len == 0) { |
| return ArrayUtils.EMPTY_STRING_ARRAY; |
| } |
| |
| if ((separator == null) || (EMPTY.equals(separator))) { |
| // Split on whitespace. |
| return splitWorker(str, null, max, preserveAllTokens); |
| } |
| |
| int separatorLength = separator.length(); |
| |
| ArrayList<String> substrings = new ArrayList<String>(); |
| int numberOfSubstrings = 0; |
| int beg = 0; |
| int end = 0; |
| while (end < len) { |
| end = str.indexOf(separator, beg); |
| |
| if (end > -1) { |
| if (end > beg) { |
| numberOfSubstrings += 1; |
| |
| if (numberOfSubstrings == max) { |
| end = len; |
| substrings.add(str.substring(beg)); |
| } else { |
| // The following is OK, because String.substring( beg, end ) excludes |
| // the character at the position 'end'. |
| substrings.add(str.substring(beg, end)); |
| |
| // Set the starting point for the next search. |
| // The following is equivalent to beg = end + (separatorLength - 1) + 1, |
| // which is the right calculation: |
| beg = end + separatorLength; |
| } |
| } else { |
| // We found a consecutive occurrence of the separator, so skip it. |
| if (preserveAllTokens) { |
| numberOfSubstrings += 1; |
| if (numberOfSubstrings == max) { |
| end = len; |
| substrings.add(str.substring(beg)); |
| } else { |
| substrings.add(EMPTY); |
| } |
| } |
| beg = end + separatorLength; |
| } |
| } else { |
| // String.substring( beg ) goes from 'beg' to the end of the String. |
| substrings.add(str.substring(beg)); |
| end = len; |
| } |
| } |
| |
| return substrings.toArray(new String[substrings.size()]); |
| } |
| |
| // ----------------------------------------------------------------------- |
| /** |
| * <p>Splits the provided text into an array, using whitespace as the |
| * separator, preserving all tokens, including empty tokens created by |
| * adjacent separators. This is an alternative to using StringTokenizer. |
| * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.splitPreserveAllTokens(null) = null |
| * StringUtils.splitPreserveAllTokens("") = [] |
| * StringUtils.splitPreserveAllTokens("abc def") = ["abc", "def"] |
| * StringUtils.splitPreserveAllTokens("abc def") = ["abc", "", "def"] |
| * StringUtils.splitPreserveAllTokens(" abc ") = ["", "abc", ""] |
| * </pre> |
| * |
| * @param str the String to parse, may be {@code null} |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String[] splitPreserveAllTokens(String str) { |
| return splitWorker(str, null, -1, true); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separator specified, |
| * preserving all tokens, including empty tokens created by adjacent |
| * separators. This is an alternative to using StringTokenizer.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.splitPreserveAllTokens(null, *) = null |
| * StringUtils.splitPreserveAllTokens("", *) = [] |
| * StringUtils.splitPreserveAllTokens("a.b.c", '.') = ["a", "b", "c"] |
| * StringUtils.splitPreserveAllTokens("a..b.c", '.') = ["a", "", "b", "c"] |
| * StringUtils.splitPreserveAllTokens("a:b:c", '.') = ["a:b:c"] |
| * StringUtils.splitPreserveAllTokens("a\tb\nc", null) = ["a", "b", "c"] |
| * StringUtils.splitPreserveAllTokens("a b c", ' ') = ["a", "b", "c"] |
| * StringUtils.splitPreserveAllTokens("a b c ", ' ') = ["a", "b", "c", ""] |
| * StringUtils.splitPreserveAllTokens("a b c ", ' ') = ["a", "b", "c", "", ""] |
| * StringUtils.splitPreserveAllTokens(" a b c", ' ') = ["", a", "b", "c"] |
| * StringUtils.splitPreserveAllTokens(" a b c", ' ') = ["", "", a", "b", "c"] |
| * StringUtils.splitPreserveAllTokens(" a b c ", ' ') = ["", a", "b", "c", ""] |
| * </pre> |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separatorChar the character used as the delimiter, |
| * {@code null} splits on whitespace |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String[] splitPreserveAllTokens(String str, char separatorChar) { |
| return splitWorker(str, separatorChar, true); |
| } |
| |
| /** |
| * Performs the logic for the {@code split} and |
| * {@code splitPreserveAllTokens} methods that do not return a |
| * maximum array length. |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separatorChar the separate character |
| * @param preserveAllTokens if {@code true}, adjacent separators are |
| * treated as empty token separators; if {@code false}, adjacent |
| * separators are treated as one separator. |
| * @return an array of parsed Strings, {@code null} if null String input |
| */ |
| private static String[] splitWorker(String str, char separatorChar, boolean preserveAllTokens) { |
| // Performance tuned for 2.0 (JDK1.4) |
| |
| if (str == null) { |
| return null; |
| } |
| int len = str.length(); |
| if (len == 0) { |
| return ArrayUtils.EMPTY_STRING_ARRAY; |
| } |
| List<String> list = new ArrayList<String>(); |
| int i = 0, start = 0; |
| boolean match = false; |
| boolean lastMatch = false; |
| while (i < len) { |
| if (str.charAt(i) == separatorChar) { |
| if (match || preserveAllTokens) { |
| list.add(str.substring(start, i)); |
| match = false; |
| lastMatch = true; |
| } |
| start = ++i; |
| continue; |
| } |
| lastMatch = false; |
| match = true; |
| i++; |
| } |
| if (match || (preserveAllTokens && lastMatch)) { |
| list.add(str.substring(start, i)); |
| } |
| return list.toArray(new String[list.size()]); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array, separators specified, |
| * preserving all tokens, including empty tokens created by adjacent |
| * separators. This is an alternative to using StringTokenizer.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * For more control over the split use the StrTokenizer class.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separatorChars splits on whitespace.</p> |
| * |
| * <pre> |
| * StringUtils.splitPreserveAllTokens(null, *) = null |
| * StringUtils.splitPreserveAllTokens("", *) = [] |
| * StringUtils.splitPreserveAllTokens("abc def", null) = ["abc", "def"] |
| * StringUtils.splitPreserveAllTokens("abc def", " ") = ["abc", "def"] |
| * StringUtils.splitPreserveAllTokens("abc def", " ") = ["abc", "", def"] |
| * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":") = ["ab", "cd", "ef"] |
| * StringUtils.splitPreserveAllTokens("ab:cd:ef:", ":") = ["ab", "cd", "ef", ""] |
| * StringUtils.splitPreserveAllTokens("ab:cd:ef::", ":") = ["ab", "cd", "ef", "", ""] |
| * StringUtils.splitPreserveAllTokens("ab::cd:ef", ":") = ["ab", "", cd", "ef"] |
| * StringUtils.splitPreserveAllTokens(":cd:ef", ":") = ["", cd", "ef"] |
| * StringUtils.splitPreserveAllTokens("::cd:ef", ":") = ["", "", cd", "ef"] |
| * StringUtils.splitPreserveAllTokens(":cd:ef:", ":") = ["", cd", "ef", ""] |
| * </pre> |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separatorChars the characters used as the delimiters, |
| * {@code null} splits on whitespace |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String[] splitPreserveAllTokens(String str, String separatorChars) { |
| return splitWorker(str, separatorChars, -1, true); |
| } |
| |
| /** |
| * <p>Splits the provided text into an array with a maximum length, |
| * separators specified, preserving all tokens, including empty tokens |
| * created by adjacent separators.</p> |
| * |
| * <p>The separator is not included in the returned String array. |
| * Adjacent separators are treated as separators for empty tokens. |
| * Adjacent separators are treated as one separator.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}. |
| * A {@code null} separatorChars splits on whitespace.</p> |
| * |
| * <p>If more than {@code max} delimited substrings are found, the last |
| * returned string includes all characters after the first {@code max - 1} |
| * returned strings (including separator characters).</p> |
| * |
| * <pre> |
| * StringUtils.splitPreserveAllTokens(null, *, *) = null |
| * StringUtils.splitPreserveAllTokens("", *, *) = [] |
| * StringUtils.splitPreserveAllTokens("ab de fg", null, 0) = ["ab", "cd", "ef"] |
| * StringUtils.splitPreserveAllTokens("ab de fg", null, 0) = ["ab", "cd", "ef"] |
| * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":", 0) = ["ab", "cd", "ef"] |
| * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":", 2) = ["ab", "cd:ef"] |
| * StringUtils.splitPreserveAllTokens("ab de fg", null, 2) = ["ab", " de fg"] |
| * StringUtils.splitPreserveAllTokens("ab de fg", null, 3) = ["ab", "", " de fg"] |
| * StringUtils.splitPreserveAllTokens("ab de fg", null, 4) = ["ab", "", "", "de fg"] |
| * </pre> |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separatorChars the characters used as the delimiters, |
| * {@code null} splits on whitespace |
| * @param max the maximum number of elements to include in the |
| * array. A zero or negative value implies no limit |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String[] splitPreserveAllTokens(String str, String separatorChars, int max) { |
| return splitWorker(str, separatorChars, max, true); |
| } |
| |
| /** |
| * Performs the logic for the {@code split} and |
| * {@code splitPreserveAllTokens} methods that return a maximum array |
| * length. |
| * |
| * @param str the String to parse, may be {@code null} |
| * @param separatorChars the separate character |
| * @param max the maximum number of elements to include in the |
| * array. A zero or negative value implies no limit. |
| * @param preserveAllTokens if {@code true}, adjacent separators are |
| * treated as empty token separators; if {@code false}, adjacent |
| * separators are treated as one separator. |
| * @return an array of parsed Strings, {@code null} if null String input |
| */ |
| private static String[] splitWorker(String str, String separatorChars, int max, boolean preserveAllTokens) { |
| // Performance tuned for 2.0 (JDK1.4) |
| // Direct code is quicker than StringTokenizer. |
| // Also, StringTokenizer uses isSpace() not isWhitespace() |
| |
| if (str == null) { |
| return null; |
| } |
| int len = str.length(); |
| if (len == 0) { |
| return ArrayUtils.EMPTY_STRING_ARRAY; |
| } |
| List<String> list = new ArrayList<String>(); |
| int sizePlus1 = 1; |
| int i = 0, start = 0; |
| boolean match = false; |
| boolean lastMatch = false; |
| if (separatorChars == null) { |
| // Null separator means use whitespace |
| while (i < len) { |
| if (Character.isWhitespace(str.charAt(i))) { |
| if (match || preserveAllTokens) { |
| lastMatch = true; |
| if (sizePlus1++ == max) { |
| i = len; |
| lastMatch = false; |
| } |
| list.add(str.substring(start, i)); |
| match = false; |
| } |
| start = ++i; |
| continue; |
| } |
| lastMatch = false; |
| match = true; |
| i++; |
| } |
| } else if (separatorChars.length() == 1) { |
| // Optimise 1 character case |
| char sep = separatorChars.charAt(0); |
| while (i < len) { |
| if (str.charAt(i) == sep) { |
| if (match || preserveAllTokens) { |
| lastMatch = true; |
| if (sizePlus1++ == max) { |
| i = len; |
| lastMatch = false; |
| } |
| list.add(str.substring(start, i)); |
| match = false; |
| } |
| start = ++i; |
| continue; |
| } |
| lastMatch = false; |
| match = true; |
| i++; |
| } |
| } else { |
| // standard case |
| while (i < len) { |
| if (separatorChars.indexOf(str.charAt(i)) >= 0) { |
| if (match || preserveAllTokens) { |
| lastMatch = true; |
| if (sizePlus1++ == max) { |
| i = len; |
| lastMatch = false; |
| } |
| list.add(str.substring(start, i)); |
| match = false; |
| } |
| start = ++i; |
| continue; |
| } |
| lastMatch = false; |
| match = true; |
| i++; |
| } |
| } |
| if (match || (preserveAllTokens && lastMatch)) { |
| list.add(str.substring(start, i)); |
| } |
| return list.toArray(new String[list.size()]); |
| } |
| |
| /** |
| * <p>Splits a String by Character type as returned by |
| * {@code java.lang.Character.getType(char)}. Groups of contiguous |
| * characters of the same type are returned as complete tokens. |
| * <pre> |
| * StringUtils.splitByCharacterType(null) = null |
| * StringUtils.splitByCharacterType("") = [] |
| * StringUtils.splitByCharacterType("ab de fg") = ["ab", " ", "de", " ", "fg"] |
| * StringUtils.splitByCharacterType("ab de fg") = ["ab", " ", "de", " ", "fg"] |
| * StringUtils.splitByCharacterType("ab:cd:ef") = ["ab", ":", "cd", ":", "ef"] |
| * StringUtils.splitByCharacterType("number5") = ["number", "5"] |
| * StringUtils.splitByCharacterType("fooBar") = ["foo", "B", "ar"] |
| * StringUtils.splitByCharacterType("foo200Bar") = ["foo", "200", "B", "ar"] |
| * StringUtils.splitByCharacterType("ASFRules") = ["ASFR", "ules"] |
| * </pre> |
| * @param str the String to split, may be {@code null} |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.4 |
| */ |
| public static String[] splitByCharacterType(String str) { |
| return splitByCharacterType(str, false); |
| } |
| |
| /** |
| * <p>Splits a String by Character type as returned by |
| * {@code java.lang.Character.getType(char)}. Groups of contiguous |
| * characters of the same type are returned as complete tokens, with the |
| * following exception: the character of type |
| * {@code Character.UPPERCASE_LETTER}, if any, immediately |
| * preceding a token of type {@code Character.LOWERCASE_LETTER} |
| * will belong to the following token rather than to the preceding, if any, |
| * {@code Character.UPPERCASE_LETTER} token. |
| * <pre> |
| * StringUtils.splitByCharacterTypeCamelCase(null) = null |
| * StringUtils.splitByCharacterTypeCamelCase("") = [] |
| * StringUtils.splitByCharacterTypeCamelCase("ab de fg") = ["ab", " ", "de", " ", "fg"] |
| * StringUtils.splitByCharacterTypeCamelCase("ab de fg") = ["ab", " ", "de", " ", "fg"] |
| * StringUtils.splitByCharacterTypeCamelCase("ab:cd:ef") = ["ab", ":", "cd", ":", "ef"] |
| * StringUtils.splitByCharacterTypeCamelCase("number5") = ["number", "5"] |
| * StringUtils.splitByCharacterTypeCamelCase("fooBar") = ["foo", "Bar"] |
| * StringUtils.splitByCharacterTypeCamelCase("foo200Bar") = ["foo", "200", "Bar"] |
| * StringUtils.splitByCharacterTypeCamelCase("ASFRules") = ["ASF", "Rules"] |
| * </pre> |
| * @param str the String to split, may be {@code null} |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.4 |
| */ |
| public static String[] splitByCharacterTypeCamelCase(String str) { |
| return splitByCharacterType(str, true); |
| } |
| |
| /** |
| * <p>Splits a String by Character type as returned by |
| * {@code java.lang.Character.getType(char)}. Groups of contiguous |
| * characters of the same type are returned as complete tokens, with the |
| * following exception: if {@code camelCase} is {@code true}, |
| * the character of type {@code Character.UPPERCASE_LETTER}, if any, |
| * immediately preceding a token of type {@code Character.LOWERCASE_LETTER} |
| * will belong to the following token rather than to the preceding, if any, |
| * {@code Character.UPPERCASE_LETTER} token. |
| * @param str the String to split, may be {@code null} |
| * @param camelCase whether to use so-called "camel-case" for letter types |
| * @return an array of parsed Strings, {@code null} if null String input |
| * @since 2.4 |
| */ |
| private static String[] splitByCharacterType(String str, boolean camelCase) { |
| if (str == null) { |
| return null; |
| } |
| if (str.length() == 0) { |
| return ArrayUtils.EMPTY_STRING_ARRAY; |
| } |
| char[] c = str.toCharArray(); |
| List<String> list = new ArrayList<String>(); |
| int tokenStart = 0; |
| int currentType = Character.getType(c[tokenStart]); |
| for (int pos = tokenStart + 1; pos < c.length; pos++) { |
| int type = Character.getType(c[pos]); |
| if (type == currentType) { |
| continue; |
| } |
| if (camelCase && type == Character.LOWERCASE_LETTER && currentType == Character.UPPERCASE_LETTER) { |
| int newTokenStart = pos - 1; |
| if (newTokenStart != tokenStart) { |
| list.add(new String(c, tokenStart, newTokenStart - tokenStart)); |
| tokenStart = newTokenStart; |
| } |
| } else { |
| list.add(new String(c, tokenStart, pos - tokenStart)); |
| tokenStart = pos; |
| } |
| currentType = type; |
| } |
| list.add(new String(c, tokenStart, c.length - tokenStart)); |
| return list.toArray(new String[list.size()]); |
| } |
| |
| // Joining |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Joins the elements of the provided array into a single String |
| * containing the provided list of elements.</p> |
| * |
| * <p>No separator is added to the joined String. |
| * Null objects or empty strings within the array are represented by |
| * empty strings.</p> |
| * |
| * <pre> |
| * StringUtils.join(null) = null |
| * StringUtils.join([]) = "" |
| * StringUtils.join([null]) = "" |
| * StringUtils.join(["a", "b", "c"]) = "abc" |
| * StringUtils.join([null, "", "a"]) = "a" |
| * </pre> |
| * |
| * @param <T> the specific type of values to join together |
| * @param elements the values to join together, may be null |
| * @return the joined String, {@code null} if null array input |
| * @since 2.0 |
| * @since 3.0 Changed signature to use varargs |
| */ |
| public static <T> String join(T... elements) { |
| return join(elements, null); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided array into a single String |
| * containing the provided list of elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * Null objects or empty strings within the array are represented by |
| * empty strings.</p> |
| * |
| * <pre> |
| * StringUtils.join(null, *) = null |
| * StringUtils.join([], *) = "" |
| * StringUtils.join([null], *) = "" |
| * StringUtils.join(["a", "b", "c"], ';') = "a;b;c" |
| * StringUtils.join(["a", "b", "c"], null) = "abc" |
| * StringUtils.join([null, "", "a"], ';') = ";;a" |
| * </pre> |
| * |
| * @param array the array of values to join together, may be null |
| * @param separator the separator character to use |
| * @return the joined String, {@code null} if null array input |
| * @since 2.0 |
| */ |
| public static String join(Object[] array, char separator) { |
| if (array == null) { |
| return null; |
| } |
| |
| return join(array, separator, 0, array.length); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided array into a single String |
| * containing the provided list of elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * Null objects or empty strings within the array are represented by |
| * empty strings.</p> |
| * |
| * <pre> |
| * StringUtils.join(null, *) = null |
| * StringUtils.join([], *) = "" |
| * StringUtils.join([null], *) = "" |
| * StringUtils.join(["a", "b", "c"], ';') = "a;b;c" |
| * StringUtils.join(["a", "b", "c"], null) = "abc" |
| * StringUtils.join([null, "", "a"], ';') = ";;a" |
| * </pre> |
| * |
| * @param array the array of values to join together, may be null |
| * @param separator the separator character to use |
| * @param startIndex the first index to start joining from. It is |
| * an error to pass in an end index past the end of the array |
| * @param endIndex the index to stop joining from (exclusive). It is |
| * an error to pass in an end index past the end of the array |
| * @return the joined String, {@code null} if null array input |
| * @since 2.0 |
| */ |
| public static String join(Object[] array, char separator, int startIndex, int endIndex) { |
| if (array == null) { |
| return null; |
| } |
| int noOfItems = (endIndex - startIndex); |
| if (noOfItems <= 0) { |
| return EMPTY; |
| } |
| |
| StringBuilder buf = new StringBuilder(noOfItems * 16); |
| |
| for (int i = startIndex; i < endIndex; i++) { |
| if (i > startIndex) { |
| buf.append(separator); |
| } |
| if (array[i] != null) { |
| buf.append(array[i]); |
| } |
| } |
| return buf.toString(); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided array into a single String |
| * containing the provided list of elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * A {@code null} separator is the same as an empty String (""). |
| * Null objects or empty strings within the array are represented by |
| * empty strings.</p> |
| * |
| * <pre> |
| * StringUtils.join(null, *) = null |
| * StringUtils.join([], *) = "" |
| * StringUtils.join([null], *) = "" |
| * StringUtils.join(["a", "b", "c"], "--") = "a--b--c" |
| * StringUtils.join(["a", "b", "c"], null) = "abc" |
| * StringUtils.join(["a", "b", "c"], "") = "abc" |
| * StringUtils.join([null, "", "a"], ',') = ",,a" |
| * </pre> |
| * |
| * @param array the array of values to join together, may be null |
| * @param separator the separator character to use, null treated as "" |
| * @return the joined String, {@code null} if null array input |
| */ |
| public static String join(Object[] array, String separator) { |
| if (array == null) { |
| return null; |
| } |
| return join(array, separator, 0, array.length); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided array into a single String |
| * containing the provided list of elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * A {@code null} separator is the same as an empty String (""). |
| * Null objects or empty strings within the array are represented by |
| * empty strings.</p> |
| * |
| * <pre> |
| * StringUtils.join(null, *) = null |
| * StringUtils.join([], *) = "" |
| * StringUtils.join([null], *) = "" |
| * StringUtils.join(["a", "b", "c"], "--") = "a--b--c" |
| * StringUtils.join(["a", "b", "c"], null) = "abc" |
| * StringUtils.join(["a", "b", "c"], "") = "abc" |
| * StringUtils.join([null, "", "a"], ',') = ",,a" |
| * </pre> |
| * |
| * @param array the array of values to join together, may be null |
| * @param separator the separator character to use, null treated as "" |
| * @param startIndex the first index to start joining from. It is |
| * an error to pass in an end index past the end of the array |
| * @param endIndex the index to stop joining from (exclusive). It is |
| * an error to pass in an end index past the end of the array |
| * @return the joined String, {@code null} if null array input |
| */ |
| public static String join(Object[] array, String separator, int startIndex, int endIndex) { |
| if (array == null) { |
| return null; |
| } |
| if (separator == null) { |
| separator = EMPTY; |
| } |
| |
| // endIndex - startIndex > 0: Len = NofStrings *(len(firstString) + len(separator)) |
| // (Assuming that all Strings are roughly equally long) |
| int noOfItems = (endIndex - startIndex); |
| if (noOfItems <= 0) { |
| return EMPTY; |
| } |
| |
| StringBuilder buf = new StringBuilder(noOfItems * 16); |
| |
| for (int i = startIndex; i < endIndex; i++) { |
| if (i > startIndex) { |
| buf.append(separator); |
| } |
| if (array[i] != null) { |
| buf.append(array[i]); |
| } |
| } |
| return buf.toString(); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided {@code Iterator} into |
| * a single String containing the provided elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. Null objects or empty |
| * strings within the iteration are represented by empty strings.</p> |
| * |
| * <p>See the examples here: {@link #join(Object[],char)}. </p> |
| * |
| * @param iterator the {@code Iterator} of values to join together, may be null |
| * @param separator the separator character to use |
| * @return the joined String, {@code null} if null iterator input |
| * @since 2.0 |
| */ |
| public static String join(Iterator<?> iterator, char separator) { |
| |
| // handle null, zero and one elements before building a buffer |
| if (iterator == null) { |
| return null; |
| } |
| if (!iterator.hasNext()) { |
| return EMPTY; |
| } |
| Object first = iterator.next(); |
| if (!iterator.hasNext()) { |
| return ObjectUtils.toString(first); |
| } |
| |
| // two or more elements |
| StringBuilder buf = new StringBuilder(256); // Java default is 16, probably too small |
| if (first != null) { |
| buf.append(first); |
| } |
| |
| while (iterator.hasNext()) { |
| buf.append(separator); |
| Object obj = iterator.next(); |
| if (obj != null) { |
| buf.append(obj); |
| } |
| } |
| |
| return buf.toString(); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided {@code Iterator} into |
| * a single String containing the provided elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * A {@code null} separator is the same as an empty String ("").</p> |
| * |
| * <p>See the examples here: {@link #join(Object[],String)}. </p> |
| * |
| * @param iterator the {@code Iterator} of values to join together, may be null |
| * @param separator the separator character to use, null treated as "" |
| * @return the joined String, {@code null} if null iterator input |
| */ |
| public static String join(Iterator<?> iterator, String separator) { |
| |
| // handle null, zero and one elements before building a buffer |
| if (iterator == null) { |
| return null; |
| } |
| if (!iterator.hasNext()) { |
| return EMPTY; |
| } |
| Object first = iterator.next(); |
| if (!iterator.hasNext()) { |
| return ObjectUtils.toString(first); |
| } |
| |
| // two or more elements |
| StringBuilder buf = new StringBuilder(256); // Java default is 16, probably too small |
| if (first != null) { |
| buf.append(first); |
| } |
| |
| while (iterator.hasNext()) { |
| if (separator != null) { |
| buf.append(separator); |
| } |
| Object obj = iterator.next(); |
| if (obj != null) { |
| buf.append(obj); |
| } |
| } |
| return buf.toString(); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided {@code Iterable} into |
| * a single String containing the provided elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. Null objects or empty |
| * strings within the iteration are represented by empty strings.</p> |
| * |
| * <p>See the examples here: {@link #join(Object[],char)}. </p> |
| * |
| * @param iterable the {@code Iterable} providing the values to join together, may be null |
| * @param separator the separator character to use |
| * @return the joined String, {@code null} if null iterator input |
| * @since 2.3 |
| */ |
| public static String join(Iterable<?> iterable, char separator) { |
| if (iterable == null) { |
| return null; |
| } |
| return join(iterable.iterator(), separator); |
| } |
| |
| /** |
| * <p>Joins the elements of the provided {@code Iterable} into |
| * a single String containing the provided elements.</p> |
| * |
| * <p>No delimiter is added before or after the list. |
| * A {@code null} separator is the same as an empty String ("").</p> |
| * |
| * <p>See the examples here: {@link #join(Object[],String)}. </p> |
| * |
| * @param iterable the {@code Iterable} providing the values to join together, may be null |
| * @param separator the separator character to use, null treated as "" |
| * @return the joined String, {@code null} if null iterator input |
| * @since 2.3 |
| */ |
| public static String join(Iterable<?> iterable, String separator) { |
| if (iterable == null) { |
| return null; |
| } |
| return join(iterable.iterator(), separator); |
| } |
| |
| // Delete |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Deletes all whitespaces from a String as defined by |
| * {@link Character#isWhitespace(char)}.</p> |
| * |
| * <pre> |
| * StringUtils.deleteWhitespace(null) = null |
| * StringUtils.deleteWhitespace("") = "" |
| * StringUtils.deleteWhitespace("abc") = "abc" |
| * StringUtils.deleteWhitespace(" ab c ") = "abc" |
| * </pre> |
| * |
| * @param str the String to delete whitespace from, may be null |
| * @return the String without whitespaces, {@code null} if null String input |
| */ |
| public static String deleteWhitespace(String str) { |
| if (isEmpty(str)) { |
| return str; |
| } |
| int sz = str.length(); |
| char[] chs = new char[sz]; |
| int count = 0; |
| for (int i = 0; i < sz; i++) { |
| if (!Character.isWhitespace(str.charAt(i))) { |
| chs[count++] = str.charAt(i); |
| } |
| } |
| if (count == sz) { |
| return str; |
| } |
| return new String(chs, 0, count); |
| } |
| |
| // Remove |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Removes a substring only if it is at the beginning of a source string, |
| * otherwise returns the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string. |
| * A {@code null} search string will return the source string.</p> |
| * |
| * <pre> |
| * StringUtils.removeStart(null, *) = null |
| * StringUtils.removeStart("", *) = "" |
| * StringUtils.removeStart(*, null) = * |
| * StringUtils.removeStart("www.domain.com", "www.") = "domain.com" |
| * StringUtils.removeStart("domain.com", "www.") = "domain.com" |
| * StringUtils.removeStart("www.domain.com", "domain") = "www.domain.com" |
| * StringUtils.removeStart("abc", "") = "abc" |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the String to search for and remove, may be null |
| * @return the substring with the string removed if found, |
| * {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String removeStart(String str, String remove) { |
| if (isEmpty(str) || isEmpty(remove)) { |
| return str; |
| } |
| if (str.startsWith(remove)){ |
| return str.substring(remove.length()); |
| } |
| return str; |
| } |
| |
| /** |
| * <p>Case insensitive removal of a substring if it is at the beginning of a source string, |
| * otherwise returns the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string. |
| * A {@code null} search string will return the source string.</p> |
| * |
| * <pre> |
| * StringUtils.removeStartIgnoreCase(null, *) = null |
| * StringUtils.removeStartIgnoreCase("", *) = "" |
| * StringUtils.removeStartIgnoreCase(*, null) = * |
| * StringUtils.removeStartIgnoreCase("www.domain.com", "www.") = "domain.com" |
| * StringUtils.removeStartIgnoreCase("www.domain.com", "WWW.") = "domain.com" |
| * StringUtils.removeStartIgnoreCase("domain.com", "www.") = "domain.com" |
| * StringUtils.removeStartIgnoreCase("www.domain.com", "domain") = "www.domain.com" |
| * StringUtils.removeStartIgnoreCase("abc", "") = "abc" |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the String to search for (case insensitive) and remove, may be null |
| * @return the substring with the string removed if found, |
| * {@code null} if null String input |
| * @since 2.4 |
| */ |
| public static String removeStartIgnoreCase(String str, String remove) { |
| if (isEmpty(str) || isEmpty(remove)) { |
| return str; |
| } |
| if (startsWithIgnoreCase(str, remove)) { |
| return str.substring(remove.length()); |
| } |
| return str; |
| } |
| |
| /** |
| * <p>Removes a substring only if it is at the end of a source string, |
| * otherwise returns the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string. |
| * A {@code null} search string will return the source string.</p> |
| * |
| * <pre> |
| * StringUtils.removeEnd(null, *) = null |
| * StringUtils.removeEnd("", *) = "" |
| * StringUtils.removeEnd(*, null) = * |
| * StringUtils.removeEnd("www.domain.com", ".com.") = "www.domain.com" |
| * StringUtils.removeEnd("www.domain.com", ".com") = "www.domain" |
| * StringUtils.removeEnd("www.domain.com", "domain") = "www.domain.com" |
| * StringUtils.removeEnd("abc", "") = "abc" |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the String to search for and remove, may be null |
| * @return the substring with the string removed if found, |
| * {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String removeEnd(String str, String remove) { |
| if (isEmpty(str) || isEmpty(remove)) { |
| return str; |
| } |
| if (str.endsWith(remove)) { |
| return str.substring(0, str.length() - remove.length()); |
| } |
| return str; |
| } |
| |
| /** |
| * <p>Case insensitive removal of a substring if it is at the end of a source string, |
| * otherwise returns the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string. |
| * A {@code null} search string will return the source string.</p> |
| * |
| * <pre> |
| * StringUtils.removeEndIgnoreCase(null, *) = null |
| * StringUtils.removeEndIgnoreCase("", *) = "" |
| * StringUtils.removeEndIgnoreCase(*, null) = * |
| * StringUtils.removeEndIgnoreCase("www.domain.com", ".com.") = "www.domain.com" |
| * StringUtils.removeEndIgnoreCase("www.domain.com", ".com") = "www.domain" |
| * StringUtils.removeEndIgnoreCase("www.domain.com", "domain") = "www.domain.com" |
| * StringUtils.removeEndIgnoreCase("abc", "") = "abc" |
| * StringUtils.removeEndIgnoreCase("www.domain.com", ".COM") = "www.domain") |
| * StringUtils.removeEndIgnoreCase("www.domain.COM", ".com") = "www.domain") |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the String to search for (case insensitive) and remove, may be null |
| * @return the substring with the string removed if found, |
| * {@code null} if null String input |
| * @since 2.4 |
| */ |
| public static String removeEndIgnoreCase(String str, String remove) { |
| if (isEmpty(str) || isEmpty(remove)) { |
| return str; |
| } |
| if (endsWithIgnoreCase(str, remove)) { |
| return str.substring(0, str.length() - remove.length()); |
| } |
| return str; |
| } |
| |
| /** |
| * <p>Removes all occurrences of a substring from within the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string. |
| * A {@code null} remove string will return the source string. |
| * An empty ("") remove string will return the source string.</p> |
| * |
| * <pre> |
| * StringUtils.remove(null, *) = null |
| * StringUtils.remove("", *) = "" |
| * StringUtils.remove(*, null) = * |
| * StringUtils.remove(*, "") = * |
| * StringUtils.remove("queued", "ue") = "qd" |
| * StringUtils.remove("queued", "zz") = "queued" |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the String to search for and remove, may be null |
| * @return the substring with the string removed if found, |
| * {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String remove(String str, String remove) { |
| if (isEmpty(str) || isEmpty(remove)) { |
| return str; |
| } |
| return replace(str, remove, EMPTY, -1); |
| } |
| |
| /** |
| * <p>Removes all occurrences of a character from within the source string.</p> |
| * |
| * <p>A {@code null} source string will return {@code null}. |
| * An empty ("") source string will return the empty string.</p> |
| * |
| * <pre> |
| * StringUtils.remove(null, *) = null |
| * StringUtils.remove("", *) = "" |
| * StringUtils.remove("queued", 'u') = "qeed" |
| * StringUtils.remove("queued", 'z') = "queued" |
| * </pre> |
| * |
| * @param str the source String to search, may be null |
| * @param remove the char to search for and remove, may be null |
| * @return the substring with the char removed if found, |
| * {@code null} if null String input |
| * @since 2.1 |
| */ |
| public static String remove(String str, char remove) { |
| if (isEmpty(str) || str.indexOf(remove) == INDEX_NOT_FOUND) { |
| return str; |
| } |
| char[] chars = str.toCharArray(); |
| int pos = 0; |
| for (int i = 0; i < chars.length; i++) { |
| if (chars[i] != remove) { |
| chars[pos++] = chars[i]; |
| } |
| } |
| return new String(chars, 0, pos); |
| } |
| |
| // Replacing |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Replaces a String with another String inside a larger String, once.</p> |
| * |
| * <p>A {@code null} reference passed to this method is a no-op.</p> |
| * |
| * <pre> |
| * StringUtils.replaceOnce(null, *, *) = null |
| * StringUtils.replaceOnce("", *, *) = "" |
| * StringUtils.replaceOnce("any", null, *) = "any" |
| * StringUtils.replaceOnce("any", *, null) = "any" |
| * StringUtils.replaceOnce("any", "", *) = "any" |
| * StringUtils.replaceOnce("aba", "a", null) = "aba" |
| * StringUtils.replaceOnce("aba", "a", "") = "ba" |
| * StringUtils.replaceOnce("aba", "a", "z") = "zba" |
| * </pre> |
| * |
| * @see #replace(String text, String searchString, String replacement, int max) |
| * @param text text to search and replace in, may be null |
| * @param searchString the String to search for, may be null |
| * @param replacement the String to replace with, may be null |
| * @return the text with any replacements processed, |
| * {@code null} if null String input |
| */ |
| public static String replaceOnce(String text, String searchString, String replacement) { |
| return replace(text, searchString, replacement, 1); |
| } |
| |
| /** |
| * <p>Replaces all occurrences of a String within another String.</p> |
| * |
| * <p>A {@code null} reference passed to this method is a no-op.</p> |
| * |
| * <pre> |
| * StringUtils.replace(null, *, *) = null |
| * StringUtils.replace("", *, *) = "" |
| * StringUtils.replace("any", null, *) = "any" |
| * StringUtils.replace("any", *, null) = "any" |
| * StringUtils.replace("any", "", *) = "any" |
| * StringUtils.replace("aba", "a", null) = "aba" |
| * StringUtils.replace("aba", "a", "") = "b" |
| * StringUtils.replace("aba", "a", "z") = "zbz" |
| * </pre> |
| * |
| * @see #replace(String text, String searchString, String replacement, int max) |
| * @param text text to search and replace in, may be null |
| * @param searchString the String to search for, may be null |
| * @param replacement the String to replace it with, may be null |
| * @return the text with any replacements processed, |
| * {@code null} if null String input |
| */ |
| public static String replace(String text, String searchString, String replacement) { |
| return replace(text, searchString, replacement, -1); |
| } |
| |
| /** |
| * <p>Replaces a String with another String inside a larger String, |
| * for the first {@code max} values of the search String.</p> |
| * |
| * <p>A {@code null} reference passed to this method is a no-op.</p> |
| * |
| * <pre> |
| * StringUtils.replace(null, *, *, *) = null |
| * StringUtils.replace("", *, *, *) = "" |
| * StringUtils.replace("any", null, *, *) = "any" |
| * StringUtils.replace("any", *, null, *) = "any" |
| * StringUtils.replace("any", "", *, *) = "any" |
| * StringUtils.replace("any", *, *, 0) = "any" |
| * StringUtils.replace("abaa", "a", null, -1) = "abaa" |
| * StringUtils.replace("abaa", "a", "", -1) = "b" |
| * StringUtils.replace("abaa", "a", "z", 0) = "abaa" |
| * StringUtils.replace("abaa", "a", "z", 1) = "zbaa" |
| * StringUtils.replace("abaa", "a", "z", 2) = "zbza" |
| * StringUtils.replace("abaa", "a", "z", -1) = "zbzz" |
| * </pre> |
| * |
| * @param text text to search and replace in, may be null |
| * @param searchString the String to search for, may be null |
| * @param replacement the String to replace it with, may be null |
| * @param max maximum number of values to replace, or {@code -1} if no maximum |
| * @return the text with any replacements processed, |
| * {@code null} if null String input |
| */ |
| public static String replace(String text, String searchString, String replacement, int max) { |
| if (isEmpty(text) || isEmpty(searchString) || replacement == null || max == 0) { |
| return text; |
| } |
| int start = 0; |
| int end = text.indexOf(searchString, start); |
| if (end == INDEX_NOT_FOUND) { |
| return text; |
| } |
| int replLength = searchString.length(); |
| int increase = replacement.length() - replLength; |
| increase = (increase < 0 ? 0 : increase); |
| increase *= (max < 0 ? 16 : (max > 64 ? 64 : max)); |
| StringBuilder buf = new StringBuilder(text.length() + increase); |
| while (end != INDEX_NOT_FOUND) { |
| buf.append(text.substring(start, end)).append(replacement); |
| start = end + replLength; |
| if (--max == 0) { |
| break; |
| } |
| end = text.indexOf(searchString, start); |
| } |
| buf.append(text.substring(start)); |
| return buf.toString(); |
| } |
| |
| /** |
| * <p> |
| * Replaces all occurrences of Strings within another String. |
| * </p> |
| * |
| * <p> |
| * A {@code null} reference passed to this method is a no-op, or if |
| * any "search string" or "string to replace" is null, that replace will be |
| * ignored. This will not repeat. For repeating replaces, call the |
| * overloaded method. |
| * </p> |
| * |
| * <pre> |
| * StringUtils.replaceEach(null, *, *) = null |
| * StringUtils.replaceEach("", *, *) = "" |
| * StringUtils.replaceEach("aba", null, null) = "aba" |
| * StringUtils.replaceEach("aba", new String[0], null) = "aba" |
| * StringUtils.replaceEach("aba", null, new String[0]) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, null) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}) = "b" |
| * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}) = "aba" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"}) = "wcte" |
| * (example of how it does not repeat) |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}) = "dcte" |
| * </pre> |
| * |
| * @param text |
| * text to search and replace in, no-op if null |
| * @param searchList |
| * the Strings to search for, no-op if null |
| * @param replacementList |
| * the Strings to replace them with, no-op if null |
| * @return the text with any replacements processed, {@code null} if |
| * null String input |
| * @throws IllegalArgumentException |
| * if the lengths of the arrays are not the same (null is ok, |
| * and/or size 0) |
| * @since 2.4 |
| */ |
| public static String replaceEach(String text, String[] searchList, String[] replacementList) { |
| return replaceEach(text, searchList, replacementList, false, 0); |
| } |
| |
| /** |
| * <p> |
| * Replaces all occurrences of Strings within another String. |
| * </p> |
| * |
| * <p> |
| * A {@code null} reference passed to this method is a no-op, or if |
| * any "search string" or "string to replace" is null, that replace will be |
| * ignored. |
| * </p> |
| * |
| * <pre> |
| * StringUtils.replaceEach(null, *, *, *) = null |
| * StringUtils.replaceEach("", *, *, *) = "" |
| * StringUtils.replaceEach("aba", null, null, *) = "aba" |
| * StringUtils.replaceEach("aba", new String[0], null, *) = "aba" |
| * StringUtils.replaceEach("aba", null, new String[0], *) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, null, *) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}, *) = "b" |
| * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}, *) = "aba" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"}, *) = "wcte" |
| * (example of how it repeats) |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, false) = "dcte" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, true) = "tcte" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "ab"}, true) = IllegalStateException |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "ab"}, false) = "dcabe" |
| * </pre> |
| * |
| * @param text |
| * text to search and replace in, no-op if null |
| * @param searchList |
| * the Strings to search for, no-op if null |
| * @param replacementList |
| * the Strings to replace them with, no-op if null |
| * @return the text with any replacements processed, {@code null} if |
| * null String input |
| * @throws IllegalStateException |
| * if the search is repeating and there is an endless loop due |
| * to outputs of one being inputs to another |
| * @throws IllegalArgumentException |
| * if the lengths of the arrays are not the same (null is ok, |
| * and/or size 0) |
| * @since 2.4 |
| */ |
| public static String replaceEachRepeatedly(String text, String[] searchList, String[] replacementList) { |
| // timeToLive should be 0 if not used or nothing to replace, else it's |
| // the length of the replace array |
| int timeToLive = searchList == null ? 0 : searchList.length; |
| return replaceEach(text, searchList, replacementList, true, timeToLive); |
| } |
| |
| /** |
| * <p> |
| * Replaces all occurrences of Strings within another String. |
| * </p> |
| * |
| * <p> |
| * A {@code null} reference passed to this method is a no-op, or if |
| * any "search string" or "string to replace" is null, that replace will be |
| * ignored. |
| * </p> |
| * |
| * <pre> |
| * StringUtils.replaceEach(null, *, *, *) = null |
| * StringUtils.replaceEach("", *, *, *) = "" |
| * StringUtils.replaceEach("aba", null, null, *) = "aba" |
| * StringUtils.replaceEach("aba", new String[0], null, *) = "aba" |
| * StringUtils.replaceEach("aba", null, new String[0], *) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, null, *) = "aba" |
| * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}, *) = "b" |
| * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}, *) = "aba" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"}, *) = "wcte" |
| * (example of how it repeats) |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, false) = "dcte" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, true) = "tcte" |
| * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "ab"}, *) = IllegalStateException |
| * </pre> |
| * |
| * @param text |
| * text to search and replace in, no-op if null |
| * @param searchList |
| * the Strings to search for, no-op if null |
| * @param replacementList |
| * the Strings to replace them with, no-op if null |
| * @param repeat if true, then replace repeatedly |
| * until there are no more possible replacements or timeToLive < 0 |
| * @param timeToLive |
| * if less than 0 then there is a circular reference and endless |
| * loop |
| * @return the text with any replacements processed, {@code null} if |
| * null String input |
| * @throws IllegalStateException |
| * if the search is repeating and there is an endless loop due |
| * to outputs of one being inputs to another |
| * @throws IllegalArgumentException |
| * if the lengths of the arrays are not the same (null is ok, |
| * and/or size 0) |
| * @since 2.4 |
| */ |
| private static String replaceEach( |
| String text, String[] searchList, String[] replacementList, boolean repeat, int timeToLive) { |
| |
| // mchyzer Performance note: This creates very few new objects (one major goal) |
| // let me know if there are performance requests, we can create a harness to measure |
| |
| if (text == null || text.length() == 0 || searchList == null || |
| searchList.length == 0 || replacementList == null || replacementList.length == 0) { |
| return text; |
| } |
| |
| // if recursing, this shouldn't be less than 0 |
| if (timeToLive < 0) { |
| throw new IllegalStateException("Output of one loop is the input of another; " + |
| "protecting from potential StackOverflowError"); |
| } |
| |
| int searchLength = searchList.length; |
| int replacementLength = replacementList.length; |
| |
| // make sure lengths are ok, these need to be equal |
| if (searchLength != replacementLength) { |
| throw new IllegalArgumentException("Search and Replace array lengths don't match: " |
| + searchLength |
| + " vs " |
| + replacementLength); |
| } |
| |
| // keep track of which still have matches |
| boolean[] noMoreMatchesForReplIndex = new boolean[searchLength]; |
| |
| // index on index that the match was found |
| int textIndex = -1; |
| int replaceIndex = -1; |
| int tempIndex = -1; |
| |
| // index of replace array that will replace the search string found |
| // NOTE: logic duplicated below START |
| for (int i = 0; i < searchLength; i++) { |
| if (noMoreMatchesForReplIndex[i] || searchList[i] == null || |
| searchList[i].length() == 0 || replacementList[i] == null) { |
| continue; |
| } |
| tempIndex = text.indexOf(searchList[i]); |
| |
| // see if we need to keep searching for this |
| if (tempIndex == -1) { |
| noMoreMatchesForReplIndex[i] = true; |
| } else { |
| if (textIndex == -1 || tempIndex < textIndex) { |
| textIndex = tempIndex; |
| replaceIndex = i; |
| } |
| } |
| } |
| // NOTE: logic mostly below END |
| |
| // no search strings found, we are done |
| if (textIndex == -1) { |
| return text; |
| } |
| |
| int start = 0; |
| |
| // get a good guess on the size of the result buffer so it doesn't have to double if it goes over a bit |
| int increase = 0; |
| |
| // count the replacement text elements that are larger than their corresponding text being replaced |
| for (int i = 0; i < searchList.length; i++) { |
| if (searchList[i] == null || replacementList[i] == null) { |
| continue; |
| } |
| int greater = replacementList[i].length() - searchList[i].length(); |
| if (greater > 0) { |
| increase += 3 * greater; // assume 3 matches |
| } |
| } |
| // have upper-bound at 20% increase, then let Java take over |
| increase = Math.min(increase, text.length() / 5); |
| |
| StringBuilder buf = new StringBuilder(text.length() + increase); |
| |
| while (textIndex != -1) { |
| |
| for (int i = start; i < textIndex; i++) { |
| buf.append(text.charAt(i)); |
| } |
| buf.append(replacementList[replaceIndex]); |
| |
| start = textIndex + searchList[replaceIndex].length(); |
| |
| textIndex = -1; |
| replaceIndex = -1; |
| tempIndex = -1; |
| // find the next earliest match |
| // NOTE: logic mostly duplicated above START |
| for (int i = 0; i < searchLength; i++) { |
| if (noMoreMatchesForReplIndex[i] || searchList[i] == null || |
| searchList[i].length() == 0 || replacementList[i] == null) { |
| continue; |
| } |
| tempIndex = text.indexOf(searchList[i], start); |
| |
| // see if we need to keep searching for this |
| if (tempIndex == -1) { |
| noMoreMatchesForReplIndex[i] = true; |
| } else { |
| if (textIndex == -1 || tempIndex < textIndex) { |
| textIndex = tempIndex; |
| replaceIndex = i; |
| } |
| } |
| } |
| // NOTE: logic duplicated above END |
| |
| } |
| int textLength = text.length(); |
| for (int i = start; i < textLength; i++) { |
| buf.append(text.charAt(i)); |
| } |
| String result = buf.toString(); |
| if (!repeat) { |
| return result; |
| } |
| |
| return replaceEach(result, searchList, replacementList, repeat, timeToLive - 1); |
| } |
| |
| // Replace, character based |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Replaces all occurrences of a character in a String with another. |
| * This is a null-safe version of {@link String#replace(char, char)}.</p> |
| * |
| * <p>A {@code null} string input returns {@code null}. |
| * An empty ("") string input returns an empty string.</p> |
| * |
| * <pre> |
| * StringUtils.replaceChars(null, *, *) = null |
| * StringUtils.replaceChars("", *, *) = "" |
| * StringUtils.replaceChars("abcba", 'b', 'y') = "aycya" |
| * StringUtils.replaceChars("abcba", 'z', 'y') = "abcba" |
| * </pre> |
| * |
| * @param str String to replace characters in, may be null |
| * @param searchChar the character to search for, may be null |
| * @param replaceChar the character to replace, may be null |
| * @return modified String, {@code null} if null string input |
| * @since 2.0 |
| */ |
| public static String replaceChars(String str, char searchChar, char replaceChar) { |
| if (str == null) { |
| return null; |
| } |
| return str.replace(searchChar, replaceChar); |
| } |
| |
| /** |
| * <p>Replaces multiple characters in a String in one go. |
| * This method can also be used to delete characters.</p> |
| * |
| * <p>For example:<br /> |
| * <code>replaceChars("hello", "ho", "jy") = jelly</code>.</p> |
| * |
| * <p>A {@code null} string input returns {@code null}. |
| * An empty ("") string input returns an empty string. |
| * A null or empty set of search characters returns the input string.</p> |
| * |
| * <p>The length of the search characters should normally equal the length |
| * of the replace characters. |
| * If the search characters is longer, then the extra search characters |
| * are deleted. |
| * If the search characters is shorter, then the extra replace characters |
| * are ignored.</p> |
| * |
| * <pre> |
| * StringUtils.replaceChars(null, *, *) = null |
| * StringUtils.replaceChars("", *, *) = "" |
| * StringUtils.replaceChars("abc", null, *) = "abc" |
| * StringUtils.replaceChars("abc", "", *) = "abc" |
| * StringUtils.replaceChars("abc", "b", null) = "ac" |
| * StringUtils.replaceChars("abc", "b", "") = "ac" |
| * StringUtils.replaceChars("abcba", "bc", "yz") = "ayzya" |
| * StringUtils.replaceChars("abcba", "bc", "y") = "ayya" |
| * StringUtils.replaceChars("abcba", "bc", "yzx") = "ayzya" |
| * </pre> |
| * |
| * @param str String to replace characters in, may be null |
| * @param searchChars a set of characters to search for, may be null |
| * @param replaceChars a set of characters to replace, may be null |
| * @return modified String, {@code null} if null string input |
| * @since 2.0 |
| */ |
| public static String replaceChars(String str, String searchChars, String replaceChars) { |
| if (isEmpty(str) || isEmpty(searchChars)) { |
| return str; |
| } |
| if (replaceChars == null) { |
| replaceChars = EMPTY; |
| } |
| boolean modified = false; |
| int replaceCharsLength = replaceChars.length(); |
| int strLength = str.length(); |
| StringBuilder buf = new StringBuilder(strLength); |
| for (int i = 0; i < strLength; i++) { |
| char ch = str.charAt(i); |
| int index = searchChars.indexOf(ch); |
| if (index >= 0) { |
| modified = true; |
| if (index < replaceCharsLength) { |
| buf.append(replaceChars.charAt(index)); |
| } |
| } else { |
| buf.append(ch); |
| } |
| } |
| if (modified) { |
| return buf.toString(); |
| } |
| return str; |
| } |
| |
| // Overlay |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Overlays part of a String with another String.</p> |
| * |
| * <p>A {@code null} string input returns {@code null}. |
| * A negative index is treated as zero. |
| * An index greater than the string length is treated as the string length. |
| * The start index is always the smaller of the two indices.</p> |
| * |
| * <pre> |
| * StringUtils.overlay(null, *, *, *) = null |
| * StringUtils.overlay("", "abc", 0, 0) = "abc" |
| * StringUtils.overlay("abcdef", null, 2, 4) = "abef" |
| * StringUtils.overlay("abcdef", "", 2, 4) = "abef" |
| * StringUtils.overlay("abcdef", "", 4, 2) = "abef" |
| * StringUtils.overlay("abcdef", "zzzz", 2, 4) = "abzzzzef" |
| * StringUtils.overlay("abcdef", "zzzz", 4, 2) = "abzzzzef" |
| * StringUtils.overlay("abcdef", "zzzz", -1, 4) = "zzzzef" |
| * StringUtils.overlay("abcdef", "zzzz", 2, 8) = "abzzzz" |
| * StringUtils.overlay("abcdef", "zzzz", -2, -3) = "zzzzabcdef" |
| * StringUtils.overlay("abcdef", "zzzz", 8, 10) = "abcdefzzzz" |
| * </pre> |
| * |
| * @param str the String to do overlaying in, may be null |
| * @param overlay the String to overlay, may be null |
| * @param start the position to start overlaying at |
| * @param end the position to stop overlaying before |
| * @return overlayed String, {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String overlay(String str, String overlay, int start, int end) { |
| if (str == null) { |
| return null; |
| } |
| if (overlay == null) { |
| overlay = EMPTY; |
| } |
| int len = str.length(); |
| if (start < 0) { |
| start = 0; |
| } |
| if (start > len) { |
| start = len; |
| } |
| if (end < 0) { |
| end = 0; |
| } |
| if (end > len) { |
| end = len; |
| } |
| if (start > end) { |
| int temp = start; |
| start = end; |
| end = temp; |
| } |
| return new StringBuilder(len + start - end + overlay.length() + 1) |
| .append(str.substring(0, start)) |
| .append(overlay) |
| .append(str.substring(end)) |
| .toString(); |
| } |
| |
| // Chomping |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Removes one newline from end of a String if it's there, |
| * otherwise leave it alone. A newline is "{@code \n}", |
| * "{@code \r}", or "{@code \r\n}".</p> |
| * |
| * <p>NOTE: This method changed in 2.0. |
| * It now more closely matches Perl chomp.</p> |
| * |
| * <pre> |
| * StringUtils.chomp(null) = null |
| * StringUtils.chomp("") = "" |
| * StringUtils.chomp("abc \r") = "abc " |
| * StringUtils.chomp("abc\n") = "abc" |
| * StringUtils.chomp("abc\r\n") = "abc" |
| * StringUtils.chomp("abc\r\n\r\n") = "abc\r\n" |
| * StringUtils.chomp("abc\n\r") = "abc\n" |
| * StringUtils.chomp("abc\n\rabc") = "abc\n\rabc" |
| * StringUtils.chomp("\r") = "" |
| * StringUtils.chomp("\n") = "" |
| * StringUtils.chomp("\r\n") = "" |
| * </pre> |
| * |
| * @param str the String to chomp a newline from, may be null |
| * @return String without newline, {@code null} if null String input |
| */ |
| public static String chomp(String str) { |
| if (isEmpty(str)) { |
| return str; |
| } |
| |
| if (str.length() == 1) { |
| char ch = str.charAt(0); |
| if (ch == CharUtils.CR || ch == CharUtils.LF) { |
| return EMPTY; |
| } |
| return str; |
| } |
| |
| int lastIdx = str.length() - 1; |
| char last = str.charAt(lastIdx); |
| |
| if (last == CharUtils.LF) { |
| if (str.charAt(lastIdx - 1) == CharUtils.CR) { |
| lastIdx--; |
| } |
| } else if (last != CharUtils.CR) { |
| lastIdx++; |
| } |
| return str.substring(0, lastIdx); |
| } |
| |
| /** |
| * <p>Removes {@code separator} from the end of |
| * {@code str} if it's there, otherwise leave it alone.</p> |
| * |
| * <p>NOTE: This method changed in version 2.0. |
| * It now more closely matches Perl chomp. |
| * For the previous behavior, use {@link #substringBeforeLast(String, String)}. |
| * This method uses {@link String#endsWith(String)}.</p> |
| * |
| * <pre> |
| * StringUtils.chomp(null, *) = null |
| * StringUtils.chomp("", *) = "" |
| * StringUtils.chomp("foobar", "bar") = "foo" |
| * StringUtils.chomp("foobar", "baz") = "foobar" |
| * StringUtils.chomp("foo", "foo") = "" |
| * StringUtils.chomp("foo ", "foo") = "foo " |
| * StringUtils.chomp(" foo", "foo") = " " |
| * StringUtils.chomp("foo", "foooo") = "foo" |
| * StringUtils.chomp("foo", "") = "foo" |
| * StringUtils.chomp("foo", null) = "foo" |
| * </pre> |
| * |
| * @param str the String to chomp from, may be null |
| * @param separator separator String, may be null |
| * @return String without trailing separator, {@code null} if null String input |
| */ |
| public static String chomp(String str, String separator) { |
| if (isEmpty(str) || separator == null) { |
| return str; |
| } |
| if (str.endsWith(separator)) { |
| return str.substring(0, str.length() - separator.length()); |
| } |
| return str; |
| } |
| |
| // Chopping |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Remove the last character from a String.</p> |
| * |
| * <p>If the String ends in {@code \r\n}, then remove both |
| * of them.</p> |
| * |
| * <pre> |
| * StringUtils.chop(null) = null |
| * StringUtils.chop("") = "" |
| * StringUtils.chop("abc \r") = "abc " |
| * StringUtils.chop("abc\n") = "abc" |
| * StringUtils.chop("abc\r\n") = "abc" |
| * StringUtils.chop("abc") = "ab" |
| * StringUtils.chop("abc\nabc") = "abc\nab" |
| * StringUtils.chop("a") = "" |
| * StringUtils.chop("\r") = "" |
| * StringUtils.chop("\n") = "" |
| * StringUtils.chop("\r\n") = "" |
| * </pre> |
| * |
| * @param str the String to chop last character from, may be null |
| * @return String without last character, {@code null} if null String input |
| */ |
| public static String chop(String str) { |
| if (str == null) { |
| return null; |
| } |
| int strLen = str.length(); |
| if (strLen < 2) { |
| return EMPTY; |
| } |
| int lastIdx = strLen - 1; |
| String ret = str.substring(0, lastIdx); |
| char last = str.charAt(lastIdx); |
| if (last == CharUtils.LF) { |
| if (ret.charAt(lastIdx - 1) == CharUtils.CR) { |
| return ret.substring(0, lastIdx - 1); |
| } |
| } |
| return ret; |
| } |
| |
| // Conversion |
| //----------------------------------------------------------------------- |
| |
| // Padding |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Repeat a String {@code repeat} times to form a |
| * new String.</p> |
| * |
| * <pre> |
| * StringUtils.repeat(null, 2) = null |
| * StringUtils.repeat("", 0) = "" |
| * StringUtils.repeat("", 2) = "" |
| * StringUtils.repeat("a", 3) = "aaa" |
| * StringUtils.repeat("ab", 2) = "abab" |
| * StringUtils.repeat("a", -2) = "" |
| * </pre> |
| * |
| * @param str the String to repeat, may be null |
| * @param repeat number of times to repeat str, negative treated as zero |
| * @return a new String consisting of the original String repeated, |
| * {@code null} if null String input |
| */ |
| public static String repeat(String str, int repeat) { |
| // Performance tuned for 2.0 (JDK1.4) |
| |
| if (str == null) { |
| return null; |
| } |
| if (repeat <= 0) { |
| return EMPTY; |
| } |
| int inputLength = str.length(); |
| if (repeat == 1 || inputLength == 0) { |
| return str; |
| } |
| if (inputLength == 1 && repeat <= PAD_LIMIT) { |
| return repeat(str.charAt(0), repeat); |
| } |
| |
| int outputLength = inputLength * repeat; |
| switch (inputLength) { |
| case 1 : |
| return repeat(str.charAt(0), repeat); |
| case 2 : |
| char ch0 = str.charAt(0); |
| char ch1 = str.charAt(1); |
| char[] output2 = new char[outputLength]; |
| for (int i = repeat * 2 - 2; i >= 0; i--, i--) { |
| output2[i] = ch0; |
| output2[i + 1] = ch1; |
| } |
| return new String(output2); |
| default : |
| StringBuilder buf = new StringBuilder(outputLength); |
| for (int i = 0; i < repeat; i++) { |
| buf.append(str); |
| } |
| return buf.toString(); |
| } |
| } |
| |
| /** |
| * <p>Repeat a String {@code repeat} times to form a |
| * new String, with a String separator injected each time. </p> |
| * |
| * <pre> |
| * StringUtils.repeat(null, null, 2) = null |
| * StringUtils.repeat(null, "x", 2) = null |
| * StringUtils.repeat("", null, 0) = "" |
| * StringUtils.repeat("", "", 2) = "" |
| * StringUtils.repeat("", "x", 3) = "xxx" |
| * StringUtils.repeat("?", ", ", 3) = "?, ?, ?" |
| * </pre> |
| * |
| * @param str the String to repeat, may be null |
| * @param separator the String to inject, may be null |
| * @param repeat number of times to repeat str, negative treated as zero |
| * @return a new String consisting of the original String repeated, |
| * {@code null} if null String input |
| * @since 2.5 |
| */ |
| public static String repeat(String str, String separator, int repeat) { |
| if(str == null || separator == null) { |
| return repeat(str, repeat); |
| } else { |
| // given that repeat(String, int) is quite optimized, better to rely on it than try and splice this into it |
| String result = repeat(str + separator, repeat); |
| return removeEnd(result, separator); |
| } |
| } |
| |
| /** |
| * <p>Returns padding using the specified delimiter repeated |
| * to a given length.</p> |
| * |
| * <pre> |
| * StringUtils.repeat(0, 'e') = "" |
| * StringUtils.repeat(3, 'e') = "eee" |
| * StringUtils.repeat(-2, 'e') = "" |
| * </pre> |
| * |
| * <p>Note: this method doesn't not support padding with |
| * <a href="http://www.unicode.org/glossary/#supplementary_character">Unicode Supplementary Characters</a> |
| * as they require a pair of {@code char}s to be represented. |
| * If you are needing to support full I18N of your applications |
| * consider using {@link #repeat(String, int)} instead. |
| * </p> |
| * |
| * @param ch character to repeat |
| * @param repeat number of times to repeat char, negative treated as zero |
| * @return String with repeated character |
| * @see #repeat(String, int) |
| */ |
| public static String repeat(char ch, int repeat) { |
| char[] buf = new char[repeat]; |
| for (int i = repeat - 1; i >= 0; i--) { |
| buf[i] = ch; |
| } |
| return new String(buf); |
| } |
| |
| /** |
| * <p>Right pad a String with spaces (' ').</p> |
| * |
| * <p>The String is padded to the size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.rightPad(null, *) = null |
| * StringUtils.rightPad("", 3) = " " |
| * StringUtils.rightPad("bat", 3) = "bat" |
| * StringUtils.rightPad("bat", 5) = "bat " |
| * StringUtils.rightPad("bat", 1) = "bat" |
| * StringUtils.rightPad("bat", -1) = "bat" |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @return right padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| */ |
| public static String rightPad(String str, int size) { |
| return rightPad(str, size, ' '); |
| } |
| |
| /** |
| * <p>Right pad a String with a specified character.</p> |
| * |
| * <p>The String is padded to the size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.rightPad(null, *, *) = null |
| * StringUtils.rightPad("", 3, 'z') = "zzz" |
| * StringUtils.rightPad("bat", 3, 'z') = "bat" |
| * StringUtils.rightPad("bat", 5, 'z') = "batzz" |
| * StringUtils.rightPad("bat", 1, 'z') = "bat" |
| * StringUtils.rightPad("bat", -1, 'z') = "bat" |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @param padChar the character to pad with |
| * @return right padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String rightPad(String str, int size, char padChar) { |
| if (str == null) { |
| return null; |
| } |
| int pads = size - str.length(); |
| if (pads <= 0) { |
| return str; // returns original String when possible |
| } |
| if (pads > PAD_LIMIT) { |
| return rightPad(str, size, String.valueOf(padChar)); |
| } |
| return str.concat(repeat(padChar, pads)); |
| } |
| |
| /** |
| * <p>Right pad a String with a specified String.</p> |
| * |
| * <p>The String is padded to the size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.rightPad(null, *, *) = null |
| * StringUtils.rightPad("", 3, "z") = "zzz" |
| * StringUtils.rightPad("bat", 3, "yz") = "bat" |
| * StringUtils.rightPad("bat", 5, "yz") = "batyz" |
| * StringUtils.rightPad("bat", 8, "yz") = "batyzyzy" |
| * StringUtils.rightPad("bat", 1, "yz") = "bat" |
| * StringUtils.rightPad("bat", -1, "yz") = "bat" |
| * StringUtils.rightPad("bat", 5, null) = "bat " |
| * StringUtils.rightPad("bat", 5, "") = "bat " |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @param padStr the String to pad with, null or empty treated as single space |
| * @return right padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| */ |
| public static String rightPad(String str, int size, String padStr) { |
| if (str == null) { |
| return null; |
| } |
| if (isEmpty(padStr)) { |
| padStr = " "; |
| } |
| int padLen = padStr.length(); |
| int strLen = str.length(); |
| int pads = size - strLen; |
| if (pads <= 0) { |
| return str; // returns original String when possible |
| } |
| if (padLen == 1 && pads <= PAD_LIMIT) { |
| return rightPad(str, size, padStr.charAt(0)); |
| } |
| |
| if (pads == padLen) { |
| return str.concat(padStr); |
| } else if (pads < padLen) { |
| return str.concat(padStr.substring(0, pads)); |
| } else { |
| char[] padding = new char[pads]; |
| char[] padChars = padStr.toCharArray(); |
| for (int i = 0; i < pads; i++) { |
| padding[i] = padChars[i % padLen]; |
| } |
| return str.concat(new String(padding)); |
| } |
| } |
| |
| /** |
| * <p>Left pad a String with spaces (' ').</p> |
| * |
| * <p>The String is padded to the size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.leftPad(null, *) = null |
| * StringUtils.leftPad("", 3) = " " |
| * StringUtils.leftPad("bat", 3) = "bat" |
| * StringUtils.leftPad("bat", 5) = " bat" |
| * StringUtils.leftPad("bat", 1) = "bat" |
| * StringUtils.leftPad("bat", -1) = "bat" |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @return left padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| */ |
| public static String leftPad(String str, int size) { |
| return leftPad(str, size, ' '); |
| } |
| |
| /** |
| * <p>Left pad a String with a specified character.</p> |
| * |
| * <p>Pad to a size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.leftPad(null, *, *) = null |
| * StringUtils.leftPad("", 3, 'z') = "zzz" |
| * StringUtils.leftPad("bat", 3, 'z') = "bat" |
| * StringUtils.leftPad("bat", 5, 'z') = "zzbat" |
| * StringUtils.leftPad("bat", 1, 'z') = "bat" |
| * StringUtils.leftPad("bat", -1, 'z') = "bat" |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @param padChar the character to pad with |
| * @return left padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String leftPad(String str, int size, char padChar) { |
| if (str == null) { |
| return null; |
| } |
| int pads = size - str.length(); |
| if (pads <= 0) { |
| return str; // returns original String when possible |
| } |
| if (pads > PAD_LIMIT) { |
| return leftPad(str, size, String.valueOf(padChar)); |
| } |
| return repeat(padChar, pads).concat(str); |
| } |
| |
| /** |
| * <p>Left pad a String with a specified String.</p> |
| * |
| * <p>Pad to a size of {@code size}.</p> |
| * |
| * <pre> |
| * StringUtils.leftPad(null, *, *) = null |
| * StringUtils.leftPad("", 3, "z") = "zzz" |
| * StringUtils.leftPad("bat", 3, "yz") = "bat" |
| * StringUtils.leftPad("bat", 5, "yz") = "yzbat" |
| * StringUtils.leftPad("bat", 8, "yz") = "yzyzybat" |
| * StringUtils.leftPad("bat", 1, "yz") = "bat" |
| * StringUtils.leftPad("bat", -1, "yz") = "bat" |
| * StringUtils.leftPad("bat", 5, null) = " bat" |
| * StringUtils.leftPad("bat", 5, "") = " bat" |
| * </pre> |
| * |
| * @param str the String to pad out, may be null |
| * @param size the size to pad to |
| * @param padStr the String to pad with, null or empty treated as single space |
| * @return left padded String or original String if no padding is necessary, |
| * {@code null} if null String input |
| */ |
| public static String leftPad(String str, int size, String padStr) { |
| if (str == null) { |
| return null; |
| } |
| if (isEmpty(padStr)) { |
| padStr = " "; |
| } |
| int padLen = padStr.length(); |
| int strLen = str.length(); |
| int pads = size - strLen; |
| if (pads <= 0) { |
| return str; // returns original String when possible |
| } |
| if (padLen == 1 && pads <= PAD_LIMIT) { |
| return leftPad(str, size, padStr.charAt(0)); |
| } |
| |
| if (pads == padLen) { |
| return padStr.concat(str); |
| } else if (pads < padLen) { |
| return padStr.substring(0, pads).concat(str); |
| } else { |
| char[] padding = new char[pads]; |
| char[] padChars = padStr.toCharArray(); |
| for (int i = 0; i < pads; i++) { |
| padding[i] = padChars[i % padLen]; |
| } |
| return new String(padding).concat(str); |
| } |
| } |
| |
| /** |
| * Gets a CharSequence length or {@code 0} if the CharSequence is |
| * {@code null}. |
| * |
| * @param cs |
| * a CharSequence or {@code null} |
| * @return CharSequence length or {@code 0} if the CharSequence is |
| * {@code null}. |
| * @since 2.4 |
| * @since 3.0 Changed signature from length(String) to length(CharSequence) |
| */ |
| public static int length(CharSequence cs) { |
| return cs == null ? 0 : cs.length(); |
| } |
| |
| // Centering |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Centers a String in a larger String of size {@code size} |
| * using the space character (' ').<p> |
| * |
| * <p>If the size is less than the String length, the String is returned. |
| * A {@code null} String returns {@code null}. |
| * A negative size is treated as zero.</p> |
| * |
| * <p>Equivalent to {@code center(str, size, " ")}.</p> |
| * |
| * <pre> |
| * StringUtils.center(null, *) = null |
| * StringUtils.center("", 4) = " " |
| * StringUtils.center("ab", -1) = "ab" |
| * StringUtils.center("ab", 4) = " ab " |
| * StringUtils.center("abcd", 2) = "abcd" |
| * StringUtils.center("a", 4) = " a " |
| * </pre> |
| * |
| * @param str the String to center, may be null |
| * @param size the int size of new String, negative treated as zero |
| * @return centered String, {@code null} if null String input |
| */ |
| public static String center(String str, int size) { |
| return center(str, size, ' '); |
| } |
| |
| /** |
| * <p>Centers a String in a larger String of size {@code size}. |
| * Uses a supplied character as the value to pad the String with.</p> |
| * |
| * <p>If the size is less than the String length, the String is returned. |
| * A {@code null} String returns {@code null}. |
| * A negative size is treated as zero.</p> |
| * |
| * <pre> |
| * StringUtils.center(null, *, *) = null |
| * StringUtils.center("", 4, ' ') = " " |
| * StringUtils.center("ab", -1, ' ') = "ab" |
| * StringUtils.center("ab", 4, ' ') = " ab" |
| * StringUtils.center("abcd", 2, ' ') = "abcd" |
| * StringUtils.center("a", 4, ' ') = " a " |
| * StringUtils.center("a", 4, 'y') = "yayy" |
| * </pre> |
| * |
| * @param str the String to center, may be null |
| * @param size the int size of new String, negative treated as zero |
| * @param padChar the character to pad the new String with |
| * @return centered String, {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String center(String str, int size, char padChar) { |
| if (str == null || size <= 0) { |
| return str; |
| } |
| int strLen = str.length(); |
| int pads = size - strLen; |
| if (pads <= 0) { |
| return str; |
| } |
| str = leftPad(str, strLen + pads / 2, padChar); |
| str = rightPad(str, size, padChar); |
| return str; |
| } |
| |
| /** |
| * <p>Centers a String in a larger String of size {@code size}. |
| * Uses a supplied String as the value to pad the String with.</p> |
| * |
| * <p>If the size is less than the String length, the String is returned. |
| * A {@code null} String returns {@code null}. |
| * A negative size is treated as zero.</p> |
| * |
| * <pre> |
| * StringUtils.center(null, *, *) = null |
| * StringUtils.center("", 4, " ") = " " |
| * StringUtils.center("ab", -1, " ") = "ab" |
| * StringUtils.center("ab", 4, " ") = " ab" |
| * StringUtils.center("abcd", 2, " ") = "abcd" |
| * StringUtils.center("a", 4, " ") = " a " |
| * StringUtils.center("a", 4, "yz") = "yayz" |
| * StringUtils.center("abc", 7, null) = " abc " |
| * StringUtils.center("abc", 7, "") = " abc " |
| * </pre> |
| * |
| * @param str the String to center, may be null |
| * @param size the int size of new String, negative treated as zero |
| * @param padStr the String to pad the new String with, must not be null or empty |
| * @return centered String, {@code null} if null String input |
| * @throws IllegalArgumentException if padStr is {@code null} or empty |
| */ |
| public static String center(String str, int size, String padStr) { |
| if (str == null || size <= 0) { |
| return str; |
| } |
| if (isEmpty(padStr)) { |
| padStr = " "; |
| } |
| int strLen = str.length(); |
| int pads = size - strLen; |
| if (pads <= 0) { |
| return str; |
| } |
| str = leftPad(str, strLen + pads / 2, padStr); |
| str = rightPad(str, size, padStr); |
| return str; |
| } |
| |
| // Case conversion |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Converts a String to upper case as per {@link String#toUpperCase()}.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.upperCase(null) = null |
| * StringUtils.upperCase("") = "" |
| * StringUtils.upperCase("aBc") = "ABC" |
| * </pre> |
| * |
| * <p><strong>Note:</strong> As described in the documentation for {@link String#toUpperCase()}, |
| * the result of this method is affected by the current locale. |
| * For platform-independent case transformations, the method {@link #lowerCase(String, Locale)} |
| * should be used with a specific locale (e.g. {@link Locale#ENGLISH}).</p> |
| * |
| * @param str the String to upper case, may be null |
| * @return the upper cased String, {@code null} if null String input |
| */ |
| public static String upperCase(String str) { |
| if (str == null) { |
| return null; |
| } |
| return str.toUpperCase(); |
| } |
| |
| /** |
| * <p>Converts a String to upper case as per {@link String#toUpperCase(Locale)}.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.upperCase(null, Locale.ENGLISH) = null |
| * StringUtils.upperCase("", Locale.ENGLISH) = "" |
| * StringUtils.upperCase("aBc", Locale.ENGLISH) = "ABC" |
| * </pre> |
| * |
| * @param str the String to upper case, may be null |
| * @param locale the locale that defines the case transformation rules, must not be null |
| * @return the upper cased String, {@code null} if null String input |
| * @since 2.5 |
| */ |
| public static String upperCase(String str, Locale locale) { |
| if (str == null) { |
| return null; |
| } |
| return str.toUpperCase(locale); |
| } |
| |
| /** |
| * <p>Converts a String to lower case as per {@link String#toLowerCase()}.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.lowerCase(null) = null |
| * StringUtils.lowerCase("") = "" |
| * StringUtils.lowerCase("aBc") = "abc" |
| * </pre> |
| * |
| * <p><strong>Note:</strong> As described in the documentation for {@link String#toLowerCase()}, |
| * the result of this method is affected by the current locale. |
| * For platform-independent case transformations, the method {@link #lowerCase(String, Locale)} |
| * should be used with a specific locale (e.g. {@link Locale#ENGLISH}).</p> |
| * |
| * @param str the String to lower case, may be null |
| * @return the lower cased String, {@code null} if null String input |
| */ |
| public static String lowerCase(String str) { |
| if (str == null) { |
| return null; |
| } |
| return str.toLowerCase(); |
| } |
| |
| /** |
| * <p>Converts a String to lower case as per {@link String#toLowerCase(Locale)}.</p> |
| * |
| * <p>A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.lowerCase(null, Locale.ENGLISH) = null |
| * StringUtils.lowerCase("", Locale.ENGLISH) = "" |
| * StringUtils.lowerCase("aBc", Locale.ENGLISH) = "abc" |
| * </pre> |
| * |
| * @param str the String to lower case, may be null |
| * @param locale the locale that defines the case transformation rules, must not be null |
| * @return the lower cased String, {@code null} if null String input |
| * @since 2.5 |
| */ |
| public static String lowerCase(String str, Locale locale) { |
| if (str == null) { |
| return null; |
| } |
| return str.toLowerCase(locale); |
| } |
| |
| /** |
| * <p>Capitalizes a String changing the first letter to title case as |
| * per {@link Character#toTitleCase(char)}. No other letters are changed.</p> |
| * |
| * <p>For a word based algorithm, see {@link org.apache.commons.lang3.text.WordUtils#capitalize(String)}. |
| * A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.capitalize(null) = null |
| * StringUtils.capitalize("") = "" |
| * StringUtils.capitalize("cat") = "Cat" |
| * StringUtils.capitalize("cAt") = "CAt" |
| * </pre> |
| * |
| * @param str the String to capitalize, may be null |
| * @return the capitalized String, {@code null} if null String input |
| * @see org.apache.commons.lang3.text.WordUtils#capitalize(String) |
| * @see #uncapitalize(String) |
| * @since 2.0 |
| */ |
| public static String capitalize(String str) { |
| int strLen; |
| if (str == null || (strLen = str.length()) == 0) { |
| return str; |
| } |
| return new StringBuilder(strLen) |
| .append(Character.toTitleCase(str.charAt(0))) |
| .append(str.substring(1)) |
| .toString(); |
| } |
| |
| /** |
| * <p>Uncapitalizes a String changing the first letter to title case as |
| * per {@link Character#toLowerCase(char)}. No other letters are changed.</p> |
| * |
| * <p>For a word based algorithm, see {@link org.apache.commons.lang3.text.WordUtils#uncapitalize(String)}. |
| * A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.uncapitalize(null) = null |
| * StringUtils.uncapitalize("") = "" |
| * StringUtils.uncapitalize("Cat") = "cat" |
| * StringUtils.uncapitalize("CAT") = "cAT" |
| * </pre> |
| * |
| * @param str the String to uncapitalize, may be null |
| * @return the uncapitalized String, {@code null} if null String input |
| * @see org.apache.commons.lang3.text.WordUtils#uncapitalize(String) |
| * @see #capitalize(String) |
| * @since 2.0 |
| */ |
| public static String uncapitalize(String str) { |
| int strLen; |
| if (str == null || (strLen = str.length()) == 0) { |
| return str; |
| } |
| return new StringBuilder(strLen) |
| .append(Character.toLowerCase(str.charAt(0))) |
| .append(str.substring(1)) |
| .toString(); |
| } |
| |
| /** |
| * <p>Swaps the case of a String changing upper and title case to |
| * lower case, and lower case to upper case.</p> |
| * |
| * <ul> |
| * <li>Upper case character converts to Lower case</li> |
| * <li>Title case character converts to Lower case</li> |
| * <li>Lower case character converts to Upper case</li> |
| * </ul> |
| * |
| * <p>For a word based algorithm, see {@link org.apache.commons.lang3.text.WordUtils#swapCase(String)}. |
| * A {@code null} input String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.swapCase(null) = null |
| * StringUtils.swapCase("") = "" |
| * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone" |
| * </pre> |
| * |
| * <p>NOTE: This method changed in Lang version 2.0. |
| * It no longer performs a word based algorithm. |
| * If you only use ASCII, you will notice no change. |
| * That functionality is available in org.apache.commons.lang3.text.WordUtils.</p> |
| * |
| * @param str the String to swap case, may be null |
| * @return the changed String, {@code null} if null String input |
| */ |
| public static String swapCase(String str) { |
| if (StringUtils.isEmpty(str)) { |
| return str; |
| } |
| |
| char[] buffer = str.toCharArray(); |
| |
| for (int i = 0; i < buffer.length; i++) { |
| char ch = buffer[i]; |
| if (Character.isUpperCase(ch)) { |
| buffer[i] = Character.toLowerCase(ch); |
| } else if (Character.isTitleCase(ch)) { |
| buffer[i] = Character.toLowerCase(ch); |
| } else if (Character.isLowerCase(ch)) { |
| buffer[i] = Character.toUpperCase(ch); |
| } |
| } |
| return new String(buffer); |
| } |
| |
| // Count matches |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Counts how many times the substring appears in the larger string.</p> |
| * |
| * <p>A {@code null} or empty ("") String input returns {@code 0}.</p> |
| * |
| * <pre> |
| * StringUtils.countMatches(null, *) = 0 |
| * StringUtils.countMatches("", *) = 0 |
| * StringUtils.countMatches("abba", null) = 0 |
| * StringUtils.countMatches("abba", "") = 0 |
| * StringUtils.countMatches("abba", "a") = 2 |
| * StringUtils.countMatches("abba", "ab") = 1 |
| * StringUtils.countMatches("abba", "xxx") = 0 |
| * </pre> |
| * |
| * @param str the CharSequence to check, may be null |
| * @param sub the substring to count, may be null |
| * @return the number of occurrences, 0 if either CharSequence is {@code null} |
| * @since 3.0 Changed signature from countMatches(String, String) to countMatches(CharSequence, CharSequence) |
| */ |
| public static int countMatches(CharSequence str, CharSequence sub) { |
| if (isEmpty(str) || isEmpty(sub)) { |
| return 0; |
| } |
| int count = 0; |
| int idx = 0; |
| while ((idx = CharSequenceUtils.indexOf(str, sub, idx)) != INDEX_NOT_FOUND) { |
| count++; |
| idx += sub.length(); |
| } |
| return count; |
| } |
| |
| // Character Tests |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Checks if the CharSequence contains only Unicode letters.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.isAlpha(null) = false |
| * StringUtils.isAlpha("") = false |
| * StringUtils.isAlpha(" ") = false |
| * StringUtils.isAlpha("abc") = true |
| * StringUtils.isAlpha("ab2c") = false |
| * StringUtils.isAlpha("ab-c") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains letters, and is non-null |
| * @since 3.0 Changed signature from isAlpha(String) to isAlpha(CharSequence) |
| * @since 3.0 Changed "" to return false and not true |
| */ |
| public static boolean isAlpha(CharSequence cs) { |
| if (cs == null || cs.length() == 0) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (Character.isLetter(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only Unicode letters and |
| * space (' ').</p> |
| * |
| * <p>{@code null} will return {@code false} |
| * An empty CharSequence (length()=0) will return {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.isAlphaSpace(null) = false |
| * StringUtils.isAlphaSpace("") = true |
| * StringUtils.isAlphaSpace(" ") = true |
| * StringUtils.isAlphaSpace("abc") = true |
| * StringUtils.isAlphaSpace("ab c") = true |
| * StringUtils.isAlphaSpace("ab2c") = false |
| * StringUtils.isAlphaSpace("ab-c") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains letters and space, |
| * and is non-null |
| * @since 3.0 Changed signature from isAlphaSpace(String) to isAlphaSpace(CharSequence) |
| */ |
| public static boolean isAlphaSpace(CharSequence cs) { |
| if (cs == null) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if ((Character.isLetter(cs.charAt(i)) == false) && (cs.charAt(i) != ' ')) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only Unicode letters or digits.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.isAlphanumeric(null) = false |
| * StringUtils.isAlphanumeric("") = false |
| * StringUtils.isAlphanumeric(" ") = false |
| * StringUtils.isAlphanumeric("abc") = true |
| * StringUtils.isAlphanumeric("ab c") = false |
| * StringUtils.isAlphanumeric("ab2c") = true |
| * StringUtils.isAlphanumeric("ab-c") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains letters or digits, |
| * and is non-null |
| * @since 3.0 Changed signature from isAlphanumeric(String) to isAlphanumeric(CharSequence) |
| * @since 3.0 Changed "" to return false and not true |
| */ |
| public static boolean isAlphanumeric(CharSequence cs) { |
| if (cs == null || cs.length() == 0) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (Character.isLetterOrDigit(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only Unicode letters, digits |
| * or space ({@code ' '}).</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.isAlphanumericSpace(null) = false |
| * StringUtils.isAlphanumericSpace("") = true |
| * StringUtils.isAlphanumericSpace(" ") = true |
| * StringUtils.isAlphanumericSpace("abc") = true |
| * StringUtils.isAlphanumericSpace("ab c") = true |
| * StringUtils.isAlphanumericSpace("ab2c") = true |
| * StringUtils.isAlphanumericSpace("ab-c") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains letters, digits or space, |
| * and is non-null |
| * @since 3.0 Changed signature from isAlphanumericSpace(String) to isAlphanumericSpace(CharSequence) |
| */ |
| public static boolean isAlphanumericSpace(CharSequence cs) { |
| if (cs == null) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if ((Character.isLetterOrDigit(cs.charAt(i)) == false) && (cs.charAt(i) != ' ')) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only ASCII printable characters.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.isAsciiPrintable(null) = false |
| * StringUtils.isAsciiPrintable("") = true |
| * StringUtils.isAsciiPrintable(" ") = true |
| * StringUtils.isAsciiPrintable("Ceki") = true |
| * StringUtils.isAsciiPrintable("ab2c") = true |
| * StringUtils.isAsciiPrintable("!ab-c~") = true |
| * StringUtils.isAsciiPrintable("\u0020") = true |
| * StringUtils.isAsciiPrintable("\u0021") = true |
| * StringUtils.isAsciiPrintable("\u007e") = true |
| * StringUtils.isAsciiPrintable("\u007f") = false |
| * StringUtils.isAsciiPrintable("Ceki G\u00fclc\u00fc") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if every character is in the range |
| * 32 thru 126 |
| * @since 2.1 |
| * @since 3.0 Changed signature from isAsciiPrintable(String) to isAsciiPrintable(CharSequence) |
| */ |
| public static boolean isAsciiPrintable(CharSequence cs) { |
| if (cs == null) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (CharUtils.isAsciiPrintable(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only Unicode digits. |
| * A decimal point is not a Unicode digit and returns false.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.isNumeric(null) = false |
| * StringUtils.isNumeric("") = false |
| * StringUtils.isNumeric(" ") = false |
| * StringUtils.isNumeric("123") = true |
| * StringUtils.isNumeric("12 3") = false |
| * StringUtils.isNumeric("ab2c") = false |
| * StringUtils.isNumeric("12-3") = false |
| * StringUtils.isNumeric("12.3") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains digits, and is non-null |
| * @since 3.0 Changed signature from isNumeric(String) to isNumeric(CharSequence) |
| * @since 3.0 Changed "" to return false and not true |
| */ |
| public static boolean isNumeric(CharSequence cs) { |
| if (cs == null || cs.length() == 0) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (Character.isDigit(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only Unicode digits or space |
| * ({@code ' '}). |
| * A decimal point is not a Unicode digit and returns false.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.isNumericSpace(null) = false |
| * StringUtils.isNumericSpace("") = true |
| * StringUtils.isNumericSpace(" ") = true |
| * StringUtils.isNumericSpace("123") = true |
| * StringUtils.isNumericSpace("12 3") = true |
| * StringUtils.isNumericSpace("ab2c") = false |
| * StringUtils.isNumericSpace("12-3") = false |
| * StringUtils.isNumericSpace("12.3") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains digits or space, |
| * and is non-null |
| * @since 3.0 Changed signature from isNumericSpace(String) to isNumericSpace(CharSequence) |
| */ |
| public static boolean isNumericSpace(CharSequence cs) { |
| if (cs == null) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if ((Character.isDigit(cs.charAt(i)) == false) && (cs.charAt(i) != ' ')) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only whitespace.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code true}.</p> |
| * |
| * <pre> |
| * StringUtils.isWhitespace(null) = false |
| * StringUtils.isWhitespace("") = true |
| * StringUtils.isWhitespace(" ") = true |
| * StringUtils.isWhitespace("abc") = false |
| * StringUtils.isWhitespace("ab2c") = false |
| * StringUtils.isWhitespace("ab-c") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains whitespace, and is non-null |
| * @since 2.0 |
| * @since 3.0 Changed signature from isWhitespace(String) to isWhitespace(CharSequence) |
| */ |
| public static boolean isWhitespace(CharSequence cs) { |
| if (cs == null) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if ((Character.isWhitespace(cs.charAt(i)) == false)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only lowercase characters.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty CharSequence (length()=0) will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.isAllLowerCase(null) = false |
| * StringUtils.isAllLowerCase("") = false |
| * StringUtils.isAllLowerCase(" ") = false |
| * StringUtils.isAllLowerCase("abc") = true |
| * StringUtils.isAllLowerCase("abC") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains lowercase characters, and is non-null |
| * @since 2.5 |
| * @since 3.0 Changed signature from isAllLowerCase(String) to isAllLowerCase(CharSequence) |
| */ |
| public static boolean isAllLowerCase(CharSequence cs) { |
| if (cs == null || isEmpty(cs)) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (Character.isLowerCase(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * <p>Checks if the CharSequence contains only uppercase characters.</p> |
| * |
| * <p>{@code null} will return {@code false}. |
| * An empty String (length()=0) will return {@code false}.</p> |
| * |
| * <pre> |
| * StringUtils.isAllUpperCase(null) = false |
| * StringUtils.isAllUpperCase("") = false |
| * StringUtils.isAllUpperCase(" ") = false |
| * StringUtils.isAllUpperCase("ABC") = true |
| * StringUtils.isAllUpperCase("aBC") = false |
| * </pre> |
| * |
| * @param cs the CharSequence to check, may be null |
| * @return {@code true} if only contains uppercase characters, and is non-null |
| * @since 2.5 |
| * @since 3.0 Changed signature from isAllUpperCase(String) to isAllUpperCase(CharSequence) |
| */ |
| public static boolean isAllUpperCase(CharSequence cs) { |
| if (cs == null || isEmpty(cs)) { |
| return false; |
| } |
| int sz = cs.length(); |
| for (int i = 0; i < sz; i++) { |
| if (Character.isUpperCase(cs.charAt(i)) == false) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| // Defaults |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Returns either the passed in String, |
| * or if the String is {@code null}, an empty String ("").</p> |
| * |
| * <pre> |
| * StringUtils.defaultString(null) = "" |
| * StringUtils.defaultString("") = "" |
| * StringUtils.defaultString("bat") = "bat" |
| * </pre> |
| * |
| * @see ObjectUtils#toString(Object) |
| * @see String#valueOf(Object) |
| * @param str the String to check, may be null |
| * @return the passed in String, or the empty String if it |
| * was {@code null} |
| */ |
| public static String defaultString(String str) { |
| return str == null ? EMPTY : str; |
| } |
| |
| /** |
| * <p>Returns either the passed in String, or if the String is |
| * {@code null}, the value of {@code defaultStr}.</p> |
| * |
| * <pre> |
| * StringUtils.defaultString(null, "NULL") = "NULL" |
| * StringUtils.defaultString("", "NULL") = "" |
| * StringUtils.defaultString("bat", "NULL") = "bat" |
| * </pre> |
| * |
| * @see ObjectUtils#toString(Object,String) |
| * @see String#valueOf(Object) |
| * @param str the String to check, may be null |
| * @param defaultStr the default String to return |
| * if the input is {@code null}, may be null |
| * @return the passed in String, or the default if it was {@code null} |
| */ |
| public static String defaultString(String str, String defaultStr) { |
| return str == null ? defaultStr : str; |
| } |
| |
| /** |
| * <p>Returns either the passed in CharSequence, or if the CharSequence is |
| * whitespace, empty ("") or {@code null}, the value of {@code defaultStr}.</p> |
| * |
| * <pre> |
| * StringUtils.defaultIfBlank(null, "NULL") = "NULL" |
| * StringUtils.defaultIfBlank("", "NULL") = "NULL" |
| * StringUtils.defaultIfBlank(" ", "NULL") = "NULL" |
| * StringUtils.defaultIfBlank("bat", "NULL") = "bat" |
| * StringUtils.defaultIfBlank("", null) = null |
| * </pre> |
| * @param <T> the specific kind of CharSequence |
| * @param str the CharSequence to check, may be null |
| * @param defaultStr the default CharSequence to return |
| * if the input is whitespace, empty ("") or {@code null}, may be null |
| * @return the passed in CharSequence, or the default |
| * @see StringUtils#defaultString(String, String) |
| */ |
| public static <T extends CharSequence> T defaultIfBlank(T str, T defaultStr) { |
| return StringUtils.isBlank(str) ? defaultStr : str; |
| } |
| |
| /** |
| * <p>Returns either the passed in CharSequence, or if the CharSequence is |
| * empty or {@code null}, the value of {@code defaultStr}.</p> |
| * |
| * <pre> |
| * StringUtils.defaultIfEmpty(null, "NULL") = "NULL" |
| * StringUtils.defaultIfEmpty("", "NULL") = "NULL" |
| * StringUtils.defaultIfEmpty("bat", "NULL") = "bat" |
| * StringUtils.defaultIfEmpty("", null) = null |
| * </pre> |
| * @param <T> the specific kind of CharSequence |
| * @param str the CharSequence to check, may be null |
| * @param defaultStr the default CharSequence to return |
| * if the input is empty ("") or {@code null}, may be null |
| * @return the passed in CharSequence, or the default |
| * @see StringUtils#defaultString(String, String) |
| */ |
| public static <T extends CharSequence> T defaultIfEmpty(T str, T defaultStr) { |
| return StringUtils.isEmpty(str) ? defaultStr : str; |
| } |
| |
| // Reversing |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Reverses a String as per {@link StringBuilder#reverse()}.</p> |
| * |
| * <p>A {@code null} String returns {@code null}.</p> |
| * |
| * <pre> |
| * StringUtils.reverse(null) = null |
| * StringUtils.reverse("") = "" |
| * StringUtils.reverse("bat") = "tab" |
| * </pre> |
| * |
| * @param str the String to reverse, may be null |
| * @return the reversed String, {@code null} if null String input |
| */ |
| public static String reverse(String str) { |
| if (str == null) { |
| return null; |
| } |
| return new StringBuilder(str).reverse().toString(); |
| } |
| |
| /** |
| * <p>Reverses a String that is delimited by a specific character.</p> |
| * |
| * <p>The Strings between the delimiters are not reversed. |
| * Thus java.lang.String becomes String.lang.java (if the delimiter |
| * is {@code '.'}).</p> |
| * |
| * <pre> |
| * StringUtils.reverseDelimited(null, *) = null |
| * StringUtils.reverseDelimited("", *) = "" |
| * StringUtils.reverseDelimited("a.b.c", 'x') = "a.b.c" |
| * StringUtils.reverseDelimited("a.b.c", ".") = "c.b.a" |
| * </pre> |
| * |
| * @param str the String to reverse, may be null |
| * @param separatorChar the separator character to use |
| * @return the reversed String, {@code null} if null String input |
| * @since 2.0 |
| */ |
| public static String reverseDelimited(String str, char separatorChar) { |
| if (str == null) { |
| return null; |
| } |
| // could implement manually, but simple way is to reuse other, |
| // probably slower, methods. |
| String[] strs = split(str, separatorChar); |
| ArrayUtils.reverse(strs); |
| return join(strs, separatorChar); |
| } |
| |
| // Abbreviating |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Abbreviates a String using ellipses. This will turn |
| * "Now is the time for all good men" into "Now is the time for..."</p> |
| * |
| * <p>Specifically: |
| * <ul> |
| * <li>If {@code str} is less than {@code maxWidth} characters |
| * long, return it.</li> |
| * <li>Else abbreviate it to {@code (substring(str, 0, max-3) + "...")}.</li> |
| * <li>If {@code maxWidth} is less than {@code 4}, throw an |
| * {@code IllegalArgumentException}.</li> |
| * <li>In no case will it return a String of length greater than |
| * {@code maxWidth}.</li> |
| * </ul> |
| * </p> |
| * |
| * <pre> |
| * StringUtils.abbreviate(null, *) = null |
| * StringUtils.abbreviate("", 4) = "" |
| * StringUtils.abbreviate("abcdefg", 6) = "abc..." |
| * StringUtils.abbreviate("abcdefg", 7) = "abcdefg" |
| * StringUtils.abbreviate("abcdefg", 8) = "abcdefg" |
| * StringUtils.abbreviate("abcdefg", 4) = "a..." |
| * StringUtils.abbreviate("abcdefg", 3) = IllegalArgumentException |
| * </pre> |
| * |
| * @param str the String to check, may be null |
| * @param maxWidth maximum length of result String, must be at least 4 |
| * @return abbreviated String, {@code null} if null String input |
| * @throws IllegalArgumentException if the width is too small |
| * @since 2.0 |
| */ |
| public static String abbreviate(String str, int maxWidth) { |
| return abbreviate(str, 0, maxWidth); |
| } |
| |
| /** |
| * <p>Abbreviates a String using ellipses. This will turn |
| * "Now is the time for all good men" into "...is the time for..."</p> |
| * |
| * <p>Works like {@code abbreviate(String, int)}, but allows you to specify |
| * a "left edge" offset. Note that this left edge is not necessarily going to |
| * be the leftmost character in the result, or the first character following the |
| * ellipses, but it will appear somewhere in the result. |
| * |
| * <p>In no case will it return a String of length greater than |
| * {@code maxWidth}.</p> |
| * |
| * <pre> |
| * StringUtils.abbreviate(null, *, *) = null |
| * StringUtils.abbreviate("", 0, 4) = "" |
| * StringUtils.abbreviate("abcdefghijklmno", -1, 10) = "abcdefg..." |
| * StringUtils.abbreviate("abcdefghijklmno", 0, 10) = "abcdefg..." |
| * StringUtils.abbreviate("abcdefghijklmno", 1, 10) = "abcdefg..." |
| * StringUtils.abbreviate("abcdefghijklmno", 4, 10) = "abcdefg..." |
| * StringUtils.abbreviate("abcdefghijklmno", 5, 10) = "...fghi..." |
| * StringUtils.abbreviate("abcdefghijklmno", 6, 10) = "...ghij..." |
| * StringUtils.abbreviate("abcdefghijklmno", 8, 10) = "...ijklmno" |
| * StringUtils.abbreviate("abcdefghijklmno", 10, 10) = "...ijklmno" |
| * StringUtils.abbreviate("abcdefghijklmno", 12, 10) = "...ijklmno" |
| * StringUtils.abbreviate("abcdefghij", 0, 3) = IllegalArgumentException |
| * StringUtils.abbreviate("abcdefghij", 5, 6) = IllegalArgumentException |
| * </pre> |
| * |
| * @param str the String to check, may be null |
| * @param offset left edge of source String |
| * @param maxWidth maximum length of result String, must be at least 4 |
| * @return abbreviated String, {@code null} if null String input |
| * @throws IllegalArgumentException if the width is too small |
| * @since 2.0 |
| */ |
| public static String abbreviate(String str, int offset, int maxWidth) { |
| if (str == null) { |
| return null; |
| } |
| if (maxWidth < 4) { |
| throw new IllegalArgumentException("Minimum abbreviation width is 4"); |
| } |
| if (str.length() <= maxWidth) { |
| return str; |
| } |
| if (offset > str.length()) { |
| offset = str.length(); |
| } |
| if ((str.length() - offset) < (maxWidth - 3)) { |
| offset = str.length() - (maxWidth - 3); |
| } |
| final String abrevMarker = "..."; |
| if (offset <= 4) { |
| return str.substring(0, maxWidth - 3) + abrevMarker; |
| } |
| if (maxWidth < 7) { |
| throw new IllegalArgumentException("Minimum abbreviation width with offset is 7"); |
| } |
| if ((offset + (maxWidth - 3)) < str.length()) { |
| return abrevMarker + abbreviate(str.substring(offset), maxWidth - 3); |
| } |
| return abrevMarker + str.substring(str.length() - (maxWidth - 3)); |
| } |
| |
| /** |
| * <p>Abbreviates a String to the length passed, replacing the middle characters with the supplied |
| * replacement String.</p> |
| * |
| * <p>This abbreviation only occurs if the following criteria is met: |
| * <ul> |
| * <li>Neither the String for abbreviation nor the replacement String are null or empty </li> |
| * <li>The length to truncate to is less than the length of the supplied String</li> |
| * <li>The length to truncate to is greater than 0</li> |
| * <li>The abbreviated String will have enough room for the length supplied replacement String |
| * and the first and last characters of the supplied String for abbreviation</li> |
| * </ul> |
| * Otherwise, the returned String will be the same as the supplied String for abbreviation. |
| * </p> |
| * |
| * <pre> |
| * StringUtils.abbreviateMiddle(null, null, 0) = null |
| * StringUtils.abbreviateMiddle("abc", null, 0) = "abc" |
| * StringUtils.abbreviateMiddle("abc", ".", 0) = "abc" |
| * StringUtils.abbreviateMiddle("abc", ".", 3) = "abc" |
| * StringUtils.abbreviateMiddle("abcdef", ".", 4) = "ab.f" |
| * </pre> |
| * |
| * @param str the String to abbreviate, may be null |
| * @param middle the String to replace the middle characters with, may be null |
| * @param length the length to abbreviate {@code str} to. |
| * @return the abbreviated String if the above criteria is met, or the original String supplied for abbreviation. |
| * @since 2.5 |
| */ |
| public static String abbreviateMiddle(String str, String middle, int length) { |
| if (isEmpty(str) || isEmpty(middle)) { |
| return str; |
| } |
| |
| if (length >= str.length() || length < (middle.length()+2)) { |
| return str; |
| } |
| |
| int targetSting = length-middle.length(); |
| int startOffset = targetSting/2+targetSting%2; |
| int endOffset = str.length()-targetSting/2; |
| |
| StringBuilder builder = new StringBuilder(length); |
| builder.append(str.substring(0,startOffset)); |
| builder.append(middle); |
| builder.append(str.substring(endOffset)); |
| |
| return builder.toString(); |
| } |
| |
| // Difference |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Compares two Strings, and returns the portion where they differ. |
| * (More precisely, return the remainder of the second String, |
| * starting from where it's different from the first.)</p> |
| * |
| * <p>For example, |
| * {@code difference("i am a machine", "i am a robot") -> "robot"}.</p> |
| * |
| * <pre> |
| * StringUtils.difference(null, null) = null |
| * StringUtils.difference("", "") = "" |
| * StringUtils.difference("", "abc") = "abc" |
| * StringUtils.difference("abc", "") = "" |
| * StringUtils.difference("abc", "abc") = "" |
| * StringUtils.difference("ab", "abxyz") = "xyz" |
| * StringUtils.difference("abcde", "abxyz") = "xyz" |
| * StringUtils.difference("abcde", "xyz") = "xyz" |
| * </pre> |
| * |
| * @param str1 the first String, may be null |
| * @param str2 the second String, may be null |
| * @return the portion of str2 where it differs from str1; returns the |
| * empty String if they are equal |
| * @since 2.0 |
| */ |
| public static String difference(String str1, String str2) { |
| if (str1 == null) { |
| return str2; |
| } |
| if (str2 == null) { |
| return str1; |
| } |
| int at = indexOfDifference(str1, str2); |
| if (at == INDEX_NOT_FOUND) { |
| return EMPTY; |
| } |
| return str2.substring(at); |
| } |
| |
| /** |
| * <p>Compares two CharSequences, and returns the index at which the |
| * CharSequences begin to differ.</p> |
| * |
| * <p>For example, |
| * {@code indexOfDifference("i am a machine", "i am a robot") -> 7}</p> |
| * |
| * <pre> |
| * StringUtils.indexOfDifference(null, null) = -1 |
| * StringUtils.indexOfDifference("", "") = -1 |
| * StringUtils.indexOfDifference("", "abc") = 0 |
| * StringUtils.indexOfDifference("abc", "") = 0 |
| * StringUtils.indexOfDifference("abc", "abc") = -1 |
| * StringUtils.indexOfDifference("ab", "abxyz") = 2 |
| * StringUtils.indexOfDifference("abcde", "abxyz") = 2 |
| * StringUtils.indexOfDifference("abcde", "xyz") = 0 |
| * </pre> |
| * |
| * @param cs1 the first CharSequence, may be null |
| * @param cs2 the second CharSequence, may be null |
| * @return the index where cs1 and cs2 begin to differ; -1 if they are equal |
| * @since 2.0 |
| * @since 3.0 Changed signature from indexOfDifference(String, String) to |
| * indexOfDifference(CharSequence, CharSequence) |
| */ |
| public static int indexOfDifference(CharSequence cs1, CharSequence cs2) { |
| if (cs1 == cs2) { |
| return INDEX_NOT_FOUND; |
| } |
| if (cs1 == null || cs2 == null) { |
| return 0; |
| } |
| int i; |
| for (i = 0; i < cs1.length() && i < cs2.length(); ++i) { |
| if (cs1.charAt(i) != cs2.charAt(i)) { |
| break; |
| } |
| } |
| if (i < cs2.length() || i < cs1.length()) { |
| return i; |
| } |
| return INDEX_NOT_FOUND; |
| } |
| |
| /** |
| * <p>Compares all CharSequences in an array and returns the index at which the |
| * CharSequences begin to differ.</p> |
| * |
| * <p>For example, |
| * <code>indexOfDifference(new String[] {"i am a machine", "i am a robot"}) -> 7</code></p> |
| * |
| * <pre> |
| * StringUtils.indexOfDifference(null) = -1 |
| * StringUtils.indexOfDifference(new String[] {}) = -1 |
| * StringUtils.indexOfDifference(new String[] {"abc"}) = -1 |
| * StringUtils.indexOfDifference(new String[] {null, null}) = -1 |
| * StringUtils.indexOfDifference(new String[] {"", ""}) = -1 |
| * StringUtils.indexOfDifference(new String[] {"", null}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"abc", null, null}) = 0 |
| * StringUtils.indexOfDifference(new String[] {null, null, "abc"}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"", "abc"}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"abc", ""}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"abc", "abc"}) = -1 |
| * StringUtils.indexOfDifference(new String[] {"abc", "a"}) = 1 |
| * StringUtils.indexOfDifference(new String[] {"ab", "abxyz"}) = 2 |
| * StringUtils.indexOfDifference(new String[] {"abcde", "abxyz"}) = 2 |
| * StringUtils.indexOfDifference(new String[] {"abcde", "xyz"}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"xyz", "abcde"}) = 0 |
| * StringUtils.indexOfDifference(new String[] {"i am a machine", "i am a robot"}) = 7 |
| * </pre> |
| * |
| * @param css array of CharSequences, entries may be null |
| * @return the index where the strings begin to differ; -1 if they are all equal |
| * @since 2.4 |
| * @since 3.0 Changed signature from indexOfDifference(String...) to indexOfDifference(CharSequence...) |
| */ |
| public static int indexOfDifference(CharSequence... css) { |
| if (css == null || css.length <= 1) { |
| return INDEX_NOT_FOUND; |
| } |
| boolean anyStringNull = false; |
| boolean allStringsNull = true; |
| int arrayLen = css.length; |
| int shortestStrLen = Integer.MAX_VALUE; |
| int longestStrLen = 0; |
| |
| // find the min and max string lengths; this avoids checking to make |
| // sure we are not exceeding the length of the string each time through |
| // the bottom loop. |
| for (int i = 0; i < arrayLen; i++) { |
| if (css[i] == null) { |
| anyStringNull = true; |
| shortestStrLen = 0; |
| } else { |
| allStringsNull = false; |
| shortestStrLen = Math.min(css[i].length(), shortestStrLen); |
| longestStrLen = Math.max(css[i].length(), longestStrLen); |
| } |
| } |
| |
| // handle lists containing all nulls or all empty strings |
| if (allStringsNull || (longestStrLen == 0 && !anyStringNull)) { |
| return INDEX_NOT_FOUND; |
| } |
| |
| // handle lists containing some nulls or some empty strings |
| if (shortestStrLen == 0) { |
| return 0; |
| } |
| |
| // find the position with the first difference across all strings |
| int firstDiff = -1; |
| for (int stringPos = 0; stringPos < shortestStrLen; stringPos++) { |
| char comparisonChar = css[0].charAt(stringPos); |
| for (int arrayPos = 1; arrayPos < arrayLen; arrayPos++) { |
| if (css[arrayPos].charAt(stringPos) != comparisonChar) { |
| firstDiff = stringPos; |
| break; |
| } |
| } |
| if (firstDiff != -1) { |
| break; |
| } |
| } |
| |
| if (firstDiff == -1 && shortestStrLen != longestStrLen) { |
| // we compared all of the characters up to the length of the |
| // shortest string and didn't find a match, but the string lengths |
| // vary, so return the length of the shortest string. |
| return shortestStrLen; |
| } |
| return firstDiff; |
| } |
| |
| /** |
| * <p>Compares all Strings in an array and returns the initial sequence of |
| * characters that is common to all of them.</p> |
| * |
| * <p>For example, |
| * <code>getCommonPrefix(new String[] {"i am a machine", "i am a robot"}) -> "i am a "</code></p> |
| * |
| * <pre> |
| * StringUtils.getCommonPrefix(null) = "" |
| * StringUtils.getCommonPrefix(new String[] {}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"abc"}) = "abc" |
| * StringUtils.getCommonPrefix(new String[] {null, null}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"", ""}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"", null}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"abc", null, null}) = "" |
| * StringUtils.getCommonPrefix(new String[] {null, null, "abc"}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"", "abc"}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"abc", ""}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"abc", "abc"}) = "abc" |
| * StringUtils.getCommonPrefix(new String[] {"abc", "a"}) = "a" |
| * StringUtils.getCommonPrefix(new String[] {"ab", "abxyz"}) = "ab" |
| * StringUtils.getCommonPrefix(new String[] {"abcde", "abxyz"}) = "ab" |
| * StringUtils.getCommonPrefix(new String[] {"abcde", "xyz"}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"xyz", "abcde"}) = "" |
| * StringUtils.getCommonPrefix(new String[] {"i am a machine", "i am a robot"}) = "i am a " |
| * </pre> |
| * |
| * @param strs array of String objects, entries may be null |
| * @return the initial sequence of characters that are common to all Strings |
| * in the array; empty String if the array is null, the elements are all null |
| * or if there is no common prefix. |
| * @since 2.4 |
| */ |
| public static String getCommonPrefix(String... strs) { |
| if (strs == null || strs.length == 0) { |
| return EMPTY; |
| } |
| int smallestIndexOfDiff = indexOfDifference(strs); |
| if (smallestIndexOfDiff == INDEX_NOT_FOUND) { |
| // all strings were identical |
| if (strs[0] == null) { |
| return EMPTY; |
| } |
| return strs[0]; |
| } else if (smallestIndexOfDiff == 0) { |
| // there were no common initial characters |
| return EMPTY; |
| } else { |
| // we found a common initial character sequence |
| return strs[0].substring(0, smallestIndexOfDiff); |
| } |
| } |
| |
| // Misc |
| //----------------------------------------------------------------------- |
| /** |
| * <p>Find the Levenshtein distance between two Strings.</p> |
| * |
| * <p>This is the number of changes needed to change one String into |
| * another, where each change is a single character modification (deletion, |
| * insertion or substitution).</p> |
| * |
| * <p>The previous implementation of the Levenshtein distance algorithm |
| * was from <a href="http://www.merriampark.com/ld.htm">http://www.merriampark.com/ld.htm</a></p> |
| * |
| * <p>Chas Emerick has written an implementation in Java, which avoids an OutOfMemoryError |
| * which can occur when my Java implementation is used with very large strings.<br> |
| * This implementation of the Levenshtein distance algorithm |
| * is from <a href="http://www.merriampark.com/ldjava.htm">http://www.merriampark.com/ldjava.htm</a></p> |
| * |
| * <pre> |
| * StringUtils.getLevenshteinDistance(null, *) = IllegalArgumentException |
| * StringUtils.getLevenshteinDistance(*, null) = IllegalArgumentException |
| * StringUtils.getLevenshteinDistance("","") = 0 |
| * StringUtils.getLevenshteinDistance("","a") = 1 |
| * StringUtils.getLevenshteinDistance("aaapppp", "") = 7 |
| * StringUtils.getLevenshteinDistance("frog", "fog") = 1 |
| * StringUtils.getLevenshteinDistance("fly", "ant") = 3 |
| * StringUtils.getLevenshteinDistance("elephant", "hippo") = 7 |
| * StringUtils.getLevenshteinDistance("hippo", "elephant") = 7 |
| * StringUtils.getLevenshteinDistance("hippo", "zzzzzzzz") = 8 |
| * StringUtils.getLevenshteinDistance("hello", "hallo") = 1 |
| * </pre> |
| * |
| * @param s the first String, must not be null |
| * @param t the second String, must not be null |
| * @return result distance |
| * @throws IllegalArgumentException if either String input {@code null} |
| * @since 3.0 Changed signature from getLevenshteinDistance(String, String) to |
| * getLevenshteinDistance(CharSequence, CharSequence) |
| */ |
| public static int getLevenshteinDistance(CharSequence s, CharSequence t) { |
| if (s == null || t == null) { |
| throw new IllegalArgumentException("Strings must not be null"); |
| } |
| |
| /* |
| The difference between this impl. and the previous is that, rather |
| than creating and retaining a matrix of size s.length() + 1 by t.length() + 1, |
| we maintain two single-dimensional arrays of length s.length() + 1. The first, d, |
| is the 'current working' distance array that maintains the newest distance cost |
| counts as we iterate through the characters of String s. Each time we increment |
| the index of String t we are comparing, d is copied to p, the second int[]. Doing so |
| allows us to retain the previous cost counts as required by the algorithm (taking |
| the minimum of the cost count to the left, up one, and diagonally up and to the left |
| of the current cost count being calculated). (Note that the arrays aren't really |
| copied anymore, just switched...this is clearly much better than cloning an array |
| or doing a System.arraycopy() each time through the outer loop.) |
| |
| Effectively, the difference between the two implementations is this one does not |
| cause an out of memory condition when calculating the LD over two very large strings. |
| */ |
| |
| int n = s.length(); // length of s |
| int m = t.length(); // length of t |
| |
| if (n == 0) { |
| return m; |
| } else if (m == 0) { |
| return n; |
| } |
| |
| if (n > m) { |
| // swap the input strings to consume less memory |
| CharSequence tmp = s; |
| s = t; |
| t = tmp; |
| n = m; |
| m = t.length(); |
| } |
| |
| int p[] = new int[n + 1]; //'previous' cost array, horizontally |
| int d[] = new int[n + 1]; // cost array, horizontally |
| int _d[]; //placeholder to assist in swapping p and d |
| |
| // indexes into strings s and t |
| int i; // iterates through s |
| int j; // iterates through t |
| |
| char t_j; // jth character of t |
| |
| int cost; // cost |
| |
| for (i = 0; i <= n; i++) { |
| p[i] = i; |
| } |
| |
| for (j = 1; j <= m; j++) { |
| t_j = t.charAt(j - 1); |
| d[0] = j; |
| |
| for (i = 1; i <= n; i++) { |
| cost = s.charAt(i - 1) == t_j ? 0 : 1; |
| // minimum of cell to the left+1, to the top+1, diagonally left and up +cost |
| d[i] = Math.min(Math.min(d[i - 1] + 1, p[i] + 1), p[i - 1] + cost); |
| } |
| |
| // copy current distance counts to 'previous row' distance counts |
| _d = p; |
| p = d; |
| d = _d; |
| } |
| |
| // our last action in the above loop was to switch d and p, so p now |
| // actually has the most recent cost counts |
| return p[n]; |
| } |
| |
| /** |
| * <p>Find the Levenshtein distance between two Strings if it's less than or equal to a given |
| * threshold.</p> |
| * |
| * <p>This is the number of changes needed to change one String into |
| * another, where each change is a single character modification (deletion, |
| * insertion or substitution).</p> |
| * |
| * <p>This implementation follows from Algorithms on Strings, Trees and Sequences by Dan Gusfield |
| * and Chas Emerick's implementation of the Levenshtein distance algorithm from |
| * <a href="http://www.merriampark.com/ld.htm">http://www.merriampark.com/ld.htm</a></p> |
| * |
| * <pre> |
| * StringUtils.getLevenshteinDistance(null, *, *) = IllegalArgumentException |
| * StringUtils.getLevenshteinDistance(*, null, *) = IllegalArgumentException |
| * StringUtils.getLevenshteinDistance(*, *, -1) = IllegalArgumentException |
| * StringUtils.getLevenshteinDistance("","", 0) = 0 |
| * StringUtils.getLevenshteinDistance("aaapppp", "", 8) = 7 |
| * StringUtils.getLevenshteinDistance("aaapppp", "", 7) = 7 |
| * StringUtils.getLevenshteinDistance("aaapppp", "", 6)) = -1 |
| * StringUtils.getLevenshteinDistance("elephant", "hippo", 7) = 7 |
| * StringUtils.getLevenshteinDistance("elephant", "hippo", 6) = -1 |
| * StringUtils.getLevenshteinDistance("hippo", "elephant", 7) = 7 |
| * StringUtils.getLevenshteinDistance("hippo", "elephant", 6) = -1 |
| * </pre> |
| * |
| * @param s the first String, must not be null |
| * @param t the second String, must not be null |
| * @param threshold the target threshold, must not be negative |
| * @return result distance, or {@code -1} if the distance would be greater than the threshold |
| * @throws IllegalArgumentException if either String input {@code null} or negative threshold |
| */ |
| public static int getLevenshteinDistance(CharSequence s, CharSequence t, int threshold) { |
| if (s == null || t == null) { |
| throw new IllegalArgumentException("Strings must not be null"); |
| } |
| if (threshold < 0) { |
| throw new IllegalArgumentException("Threshold must not be negative"); |
| } |
| |
| /* |
| This implementation only computes the distance if it's less than or equal to the |
| threshold value, returning -1 if it's greater. The advantage is performance: unbounded |
| distance is O(nm), but a bound of k allows us to reduce it to O(km) time by only |
| computing a diagonal stripe of width 2k + 1 of the cost table. |
| It is also possible to use this to compute the unbounded Levenshtein distance by starting |
| the threshold at 1 and doubling each time until the distance is found; this is O(dm), where |
| d is the distance. |
| |
| One subtlety comes from needing to ignore entries on the border of our stripe |
| eg. |
| p[] = |#|#|#|* |
| d[] = *|#|#|#| |
| We must ignore the entry to the left of the leftmost member |
| We must ignore the entry above the rightmost member |
| |
| Another subtlety comes from our stripe running off the matrix if the strings aren't |
| of the same size. Since string s is always swapped to be the shorter of the two, |
| the stripe will always run off to the upper right instead of the lower left of the matrix. |
| |
| As a concrete example, suppose s is of length 5, t is of length 7, and our threshold is 1. |
| In this case we're going to walk a stripe of length 3. The matrix would look like so: |
| |
| 1 2 3 4 5 |
| 1 |#|#| | | | |
| 2 |#|#|#| | | |
| 3 | |#|#|#| | |
| 4 | | |#|#|#| |
| 5 | | | |#|#| |
| 6 | | | | |#| |
| 7 | | | | | | |
| |
| Note how the stripe leads off the table as there is no possible way to turn a string of length 5 |
| into one of length 7 in edit distance of 1. |
| |
| Additionally, this implementation decreases memory usage by using two |
| single-dimensional arrays and swapping them back and forth instead of allocating |
| an entire n by m matrix. This requires a few minor changes, such as immediately returning |
| when it's detected that the stripe has run off the matrix and initially filling the arrays with |
| large values so that entries we don't compute are ignored. |
| |
| See Algorithms on Strings, Trees and Sequences by Dan Gusfield for some discussion. |
| */ |
| |
| int n = s.length(); // length of s |
| int m = t.length(); // length of t |
| |
| // if one string is empty, the edit distance is necessarily the length of the other |
| if (n == 0) { |
| return m <= threshold ? m : -1; |
| } else if (m == 0) { |
| return n <= threshold ? n : -1; |
| } |
| |
| if (n > m) { |
| // swap the two strings to consume less memory |
| CharSequence tmp = s; |
| s = t; |
| t = tmp; |
| n = m; |
| m = t.length(); |
| } |
| |
| int p[] = new int[n + 1]; // 'previous' cost array, horizontally |
| int d[] = new int[n + 1]; // cost array, horizontally |
| int _d[]; // placeholder to assist in swapping p and d |
| |
| // fill in starting table values |
| int boundary = Math.min(n, threshold) + 1; |
| for (int i = 0; i < boundary; i++) { |
| p[i] = i; |
| } |
| // these fills ensure that the value above the rightmost entry of our |
| // stripe will be ignored in following loop iterations |
| Arrays.fill(p, boundary, p.length, Integer.MAX_VALUE); |
| Arrays.fill(d, Integer.MAX_VALUE); |
| |
| // iterates through t |
| for (int j = 1; j <= m; j++) { |
| char t_j = t.charAt(j - 1); // jth character of t |
| d[0] = j; |
| |
| // compute stripe indices, constrain to array size |
| int min = Math.max(1, j - threshold); |
| int max = Math.min(n, j + threshold); |
| |
| // the stripe may lead off of the table if s and t are of different sizes |
| if (min > max) { |
| return -1; |
| } |
| |
| // ignore entry left of leftmost |
| if (min > 1) { |
| d[min - 1] = Integer.MAX_VALUE; |
| } |
| |
| // iterates through [min, max] in s |
| for (int i = min; i <= max; i++) { |
| if (s.charAt(i - 1) == t_j) { |
| // diagonally left and up |
| d[i] = p[i - 1]; |
| } else { |
| // 1 + minimum of cell to the left, to the top, diagonally left and up |
| d[i] = 1 + Math.min(Math.min(d[i - 1], p[i]), p[i - 1]); |
| } |
| } |
| |
| // copy current distance counts to 'previous row' distance counts |
| _d = p; |
| p = d; |
| d = _d; |
| } |
| |
| // if p[n] is greater than the threshold, there's no guarantee on it being the correct |
| // distance |
| if (p[n] <= threshold) { |
| return p[n]; |
| } else { |
| return -1; |
| } |
| } |
| |
| // startsWith |
| //----------------------------------------------------------------------- |
| |
| /** |
| * <p>Check if a CharSequence starts with a specified prefix.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered to be equal. The comparison is case sensitive.</p> |
| * |
| * <pre> |
| * StringUtils.startsWith(null, null) = true |
| * StringUtils.startsWith(null, "abc") = false |
| * StringUtils.startsWith("abcdef", null) = false |
| * StringUtils.startsWith("abcdef", "abc") = true |
| * StringUtils.startsWith("ABCDEF", "abc") = false |
| * </pre> |
| * |
| * @see java.lang.String#startsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param prefix the prefix to find, may be null |
| * @return {@code true} if the CharSequence starts with the prefix, case sensitive, or |
| * both {@code null} |
| * @since 2.4 |
| * @since 3.0 Changed signature from startsWith(String, String) to startsWith(CharSequence, CharSequence) |
| */ |
| public static boolean startsWith(CharSequence str, CharSequence prefix) { |
| return startsWith(str, prefix, false); |
| } |
| |
| /** |
| * <p>Case insensitive check if a CharSequence starts with a specified prefix.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered to be equal. The comparison is case insensitive.</p> |
| * |
| * <pre> |
| * StringUtils.startsWithIgnoreCase(null, null) = true |
| * StringUtils.startsWithIgnoreCase(null, "abc") = false |
| * StringUtils.startsWithIgnoreCase("abcdef", null) = false |
| * StringUtils.startsWithIgnoreCase("abcdef", "abc") = true |
| * StringUtils.startsWithIgnoreCase("ABCDEF", "abc") = true |
| * </pre> |
| * |
| * @see java.lang.String#startsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param prefix the prefix to find, may be null |
| * @return {@code true} if the CharSequence starts with the prefix, case insensitive, or |
| * both {@code null} |
| * @since 2.4 |
| * @since 3.0 Changed signature from startsWithIgnoreCase(String, String) to startsWithIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static boolean startsWithIgnoreCase(CharSequence str, CharSequence prefix) { |
| return startsWith(str, prefix, true); |
| } |
| |
| /** |
| * <p>Check if a CharSequence starts with a specified prefix (optionally case insensitive).</p> |
| * |
| * @see java.lang.String#startsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param prefix the prefix to find, may be null |
| * @param ignoreCase indicates whether the compare should ignore case |
| * (case insensitive) or not. |
| * @return {@code true} if the CharSequence starts with the prefix or |
| * both {@code null} |
| */ |
| private static boolean startsWith(CharSequence str, CharSequence prefix, boolean ignoreCase) { |
| if (str == null || prefix == null) { |
| return (str == null && prefix == null); |
| } |
| if (prefix.length() > str.length()) { |
| return false; |
| } |
| return CharSequenceUtils.regionMatches(str, ignoreCase, 0, prefix, 0, prefix.length()); |
| } |
| |
| /** |
| * <p>Check if a CharSequence starts with any of an array of specified strings.</p> |
| * |
| * <pre> |
| * StringUtils.startsWithAny(null, null) = false |
| * StringUtils.startsWithAny(null, new String[] {"abc"}) = false |
| * StringUtils.startsWithAny("abcxyz", null) = false |
| * StringUtils.startsWithAny("abcxyz", new String[] {""}) = false |
| * StringUtils.startsWithAny("abcxyz", new String[] {"abc"}) = true |
| * StringUtils.startsWithAny("abcxyz", new String[] {null, "xyz", "abc"}) = true |
| * </pre> |
| * |
| * @param string the CharSequence to check, may be null |
| * @param searchStrings the CharSequences to find, may be null or empty |
| * @return {@code true} if the CharSequence starts with any of the the prefixes, case insensitive, or |
| * both {@code null} |
| * @since 2.5 |
| * @since 3.0 Changed signature from startsWithAny(String, String[]) to startsWithAny(CharSequence, CharSequence...) |
| */ |
| public static boolean startsWithAny(CharSequence string, CharSequence... searchStrings) { |
| if (isEmpty(string) || ArrayUtils.isEmpty(searchStrings)) { |
| return false; |
| } |
| for (CharSequence searchString : searchStrings) { |
| if (StringUtils.startsWith(string, searchString)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // endsWith |
| //----------------------------------------------------------------------- |
| |
| /** |
| * <p>Check if a CharSequence ends with a specified suffix.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered to be equal. The comparison is case sensitive.</p> |
| * |
| * <pre> |
| * StringUtils.endsWith(null, null) = true |
| * StringUtils.endsWith(null, "def") = false |
| * StringUtils.endsWith("abcdef", null) = false |
| * StringUtils.endsWith("abcdef", "def") = true |
| * StringUtils.endsWith("ABCDEF", "def") = false |
| * StringUtils.endsWith("ABCDEF", "cde") = false |
| * </pre> |
| * |
| * @see java.lang.String#endsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param suffix the suffix to find, may be null |
| * @return {@code true} if the CharSequence ends with the suffix, case sensitive, or |
| * both {@code null} |
| * @since 2.4 |
| * @since 3.0 Changed signature from endsWith(String, String) to endsWith(CharSequence, CharSequence) |
| */ |
| public static boolean endsWith(CharSequence str, CharSequence suffix) { |
| return endsWith(str, suffix, false); |
| } |
| |
| /** |
| * <p>Case insensitive check if a CharSequence ends with a specified suffix.</p> |
| * |
| * <p>{@code null}s are handled without exceptions. Two {@code null} |
| * references are considered to be equal. The comparison is case insensitive.</p> |
| * |
| * <pre> |
| * StringUtils.endsWithIgnoreCase(null, null) = true |
| * StringUtils.endsWithIgnoreCase(null, "def") = false |
| * StringUtils.endsWithIgnoreCase("abcdef", null) = false |
| * StringUtils.endsWithIgnoreCase("abcdef", "def") = true |
| * StringUtils.endsWithIgnoreCase("ABCDEF", "def") = true |
| * StringUtils.endsWithIgnoreCase("ABCDEF", "cde") = false |
| * </pre> |
| * |
| * @see java.lang.String#endsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param suffix the suffix to find, may be null |
| * @return {@code true} if the CharSequence ends with the suffix, case insensitive, or |
| * both {@code null} |
| * @since 2.4 |
| * @since 3.0 Changed signature from endsWithIgnoreCase(String, String) to endsWithIgnoreCase(CharSequence, CharSequence) |
| */ |
| public static boolean endsWithIgnoreCase(CharSequence str, CharSequence suffix) { |
| return endsWith(str, suffix, true); |
| } |
| |
| /** |
| * <p>Check if a CharSequence ends with a specified suffix (optionally case insensitive).</p> |
| * |
| * @see java.lang.String#endsWith(String) |
| * @param str the CharSequence to check, may be null |
| * @param suffix the suffix to find, may be null |
| * @param ignoreCase indicates whether the compare should ignore case |
| * (case insensitive) or not. |
| * @return {@code true} if the CharSequence starts with the prefix or |
| * both {@code null} |
| */ |
| private static boolean endsWith(CharSequence str, CharSequence suffix, boolean ignoreCase) { |
| if (str == null || suffix == null) { |
| return str == null && suffix == null; |
| } |
| if (suffix.length() > str.length()) { |
| return false; |
| } |
| int strOffset = str.length() - suffix.length(); |
| return CharSequenceUtils.regionMatches(str, ignoreCase, strOffset, suffix, 0, suffix.length()); |
| } |
| |
| /** |
| * <p> |
| * Similar to <a |
| * href="http://www.w3.org/TR/xpath/#function-normalize-space">http://www.w3.org/TR/xpath/#function-normalize |
| * -space</a> |
| * </p> |
| * <p> |
| * The function returns the argument string with whitespace normalized by using |
| * <code>{@link #trim(String)}</code> to remove leading and trailing whitespace |
| * and then replacing sequences of whitespace characters by a single space. |
| * </p> |
| * In XML Whitespace characters are the same as those allowed by the <a |
| * href="http://www.w3.org/TR/REC-xml/#NT-S">S</a> production, which is S ::= (#x20 | #x9 | #xD | #xA)+ |
| * <p> |
| * Java's regexp pattern \s defines whitespace as [ \t\n\x0B\f\r] |
| * <p> |
| * For reference: |
| * <ul> |
| * <li>\x0B = vertical tab</li> |
| * <li>\f = #xC = form feed</li> |
| * <li>#x20 = space</li> |
| * <li>#x9 = \t</li> |
| * <li>#xA = \n</li> |
| * <li>#xD = \r</li> |
| * </ul> |
| * </p> |
| * <p> |
| * The difference is that Java's whitespace includes vertical tab and form feed, which this functional will also |
| * normalize. Additionally <code>{@link #trim(String)}</code> removes control characters (char <= 32) from both |
| * ends of this String. |
| * </p> |
| * |
| * @see Pattern |
| * @see #trim(String) |
| * @see <a |
| * href="http://www.w3.org/TR/xpath/#function-normalize-space">http://www.w3.org/TR/xpath/#function-normalize-space</a> |
| * @param str the source String to normalize whitespaces from, may be null |
| * @return the modified string with whitespace normalized, {@code null} if null String input |
| * |
| * @since 3.0 |
| */ |
| public static String normalizeSpace(String str) { |
| if (str == null) { |
| return null; |
| } |
| return WHITESPACE_BLOCK.matcher(trim(str)).replaceAll(" "); |
| } |
| |
| /** |
| * <p>Check if a CharSequence ends with any of an array of specified strings.</p> |
| * |
| * <pre> |
| * StringUtils.endsWithAny(null, null) = false |
| * StringUtils.endsWithAny(null, new String[] {"abc"}) = false |
| * StringUtils.endsWithAny("abcxyz", null) = false |
| * StringUtils.endsWithAny("abcxyz", new String[] {""}) = true |
| * StringUtils.endsWithAny("abcxyz", new String[] {"xyz"}) = true |
| * StringUtils.endsWithAny("abcxyz", new String[] {null, "xyz", "abc"}) = true |
| * </pre> |
| * |
| * @param string the CharSequence to check, may be null |
| * @param searchStrings the CharSequences to find, may be null or empty |
| * @return {@code true} if the CharSequence ends with any of the the prefixes, case insensitive, or |
| * both {@code null} |
| * @since 3.0 |
| */ |
| public static boolean endsWithAny(CharSequence string, CharSequence... searchStrings) { |
| if (isEmpty(string) || ArrayUtils.isEmpty(searchStrings)) { |
| return false; |
| } |
| for (CharSequence searchString : searchStrings) { |
| if (StringUtils.endsWith(string, searchString)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| } |