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/*
* 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.maven.shared.utils;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Locale;
import java.util.Map;
import java.util.StringTokenizer;
/**
* <p>Common <code>String</code> manipulation routines.</p>
*
* <p>Originally from
* <a href="http://jakarta.apache.org/turbine/">Turbine</a>, the
* GenerationJavaCore library and Velocity.
* Later a lots methods from commons-lang StringUtils
* got added too. Gradually smaller additions and fixes have been made
* over the time by various ASF committers.</p>
*
* @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
* @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
* @author <a href="mailto:gcoladonato@yahoo.com">Greg Coladonato</a>
* @author <a href="mailto:bayard@generationjava.com">Henri Yandell</a>
* @author <a href="mailto:ed@apache.org">Ed Korthof</a>
* @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a>
* @author Stephen Colebourne
* @author <a href="mailto:fredrik@westermarck.com">Fredrik Westermarck</a>
* @author Holger Krauth
* @author <a href="mailto:alex@purpletech.com">Alexander Day Chaffee</a>
*
*/
public class StringUtils {
/**
* <p><code>StringUtils</code> instances should NOT be constructed in
* standard programming. Instead, the class should be used as
* <code>StringUtils.trim(" foo ");</code>.</p>
*
* <p>This constructor is public to permit tools that require a JavaBean
* manager to operate.</p>
*/
public StringUtils() {}
// Empty
// --------------------------------------------------------------------------
/**
* <p>Removes C0 control characters, including ASCII whitespace, from both
* ends of this String, handling <code>null</code> by returning
* an empty String.</p>
*
* @param str the String to check
* @return the trimmed text (never <code>null</code>)
* @see java.lang.String#trim()
*/
@Nonnull
public static String clean(String str) {
return (str == null ? "" : str.trim());
}
/**
* <p>Removes C0 control characters, including ASCII whitespace, from both
* ends of this String, handling <code>null</code> by returning
* <code>null</code>.</p>
*
* @param str the String to check
* @return the trimmed text (or <code>null</code>)
* @see java.lang.String#trim()
*/
public static String trim(String str) {
return (str == null ? null : str.trim());
}
/**
* <p>Deletes all whitespace from a String.</p>
*
* <p>Whitespace is defined by
* {@link Character#isWhitespace(char)}.</p>
*
* @param str String target to delete whitespace from
* @return the String without whitespace
*/
@Nonnull
public static String deleteWhitespace(@Nonnull String str) {
StringBuilder buffer = new StringBuilder();
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (!Character.isWhitespace(str.charAt(i))) {
buffer.append(str.charAt(i));
}
}
return buffer.toString();
}
/**
* <p>Checks if a String is non <code>null</code> and is
* not empty (<code>length &gt; 0</code>).</p>
*
* @param str the String to check
* @return true if the String is non-null, and not length zero
*/
public static boolean isNotEmpty(@Nullable String str) {
return ((str != null) && (str.length() > 0));
}
/**
* <p>Checks if a (trimmed) String is <code>null</code> or empty.</p>
*
* <p><strong>Note:</strong> In future releases, this method will no longer trim the input string such that it works
* complementary to {@link #isNotEmpty(String)}. Code that wants to test for whitespace-only strings should be
* migrated to use {@link #isBlank(String)} instead.</p>
*
* @param str the String to check
* @return <code>true</code> if the String is <code>null</code>, or
* length zero once trimmed
*/
public static boolean isEmpty(@Nullable String str) {
return ((str == null) || (str.trim().length() == 0));
}
/**
* <p>
* Checks if a String 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 str the String to check, may be null
* @return <code>true</code> if the String is null, empty or whitespace
*
*/
public static boolean isBlank(@Nullable String str) {
int strLen;
// CHECKSTYLE_OFF: InnerAssignment
if (str == null || (strLen = str.length()) == 0)
// CHECKSTYLE_ON: InnerAssignment
{
return true;
}
for (int i = 0; i < strLen; i++) {
if (!Character.isWhitespace(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if a String 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 str the String to check, may be null
* @return <code>true</code> if the String is not empty and not null and not whitespace
*
*/
public static boolean isNotBlank(@Nullable String str) {
return !isBlank(str);
}
// Equals and IndexOf
// --------------------------------------------------------------------------
/**
* <p>Compares two Strings, returning <code>true</code> if they are equal.</p>
*
* <p><code>null</code>s are handled without exceptions. Two <code>null</code>
* references are considered to be equal. The comparison is case sensitive.</p>
*
* @param str1 the first string
* @param str2 the second string
* @return <code>true</code> if the Strings are equal, case sensitive, or
* both <code>null</code>
* @see java.lang.String#equals(Object)
* @deprecated use {@code java.lang.Objects.equals()}
*/
@Deprecated
public static boolean equals(@Nullable String str1, @Nullable String str2) {
return (str1 == null ? str2 == null : str1.equals(str2));
}
/**
* <p>Compares two Strings, returning <code>true</code> if they are equal ignoring
* the case.</p>
*
* <p><code>Nulls</code> are handled without exceptions. Two <code>null</code>
* references are considered equal. Comparison is case insensitive.</p>
*
* @param str1 the first string
* @param str2 the second string
* @return <code>true</code> if the Strings are equal, case insensitive, or
* both <code>null</code>
* @see java.lang.String#equalsIgnoreCase(String)
*/
public static boolean equalsIgnoreCase(String str1, String str2) {
return (str1 == null ? str2 == null : str1.equalsIgnoreCase(str2));
}
/**
* <p>Find the first index of any of a set of potential substrings.</p>
*
* <p><code>null</code> String will return <code>-1</code>.</p>
*
* @param str the String to check
* @param searchStrs the Strings to search for
* @return the first index of any of the searchStrs in str
* @throws NullPointerException if any of searchStrs[i] is <code>null</code>
*/
public static int indexOfAny(String str, String... searchStrs) {
if ((str == null) || (searchStrs == null)) {
return -1;
}
// String's can't have a MAX_VALUEth index.
int ret = Integer.MAX_VALUE;
int tmp;
for (String searchStr : searchStrs) {
tmp = str.indexOf(searchStr);
if (tmp == -1) {
continue;
}
if (tmp < ret) {
ret = tmp;
}
}
return (ret == Integer.MAX_VALUE) ? -1 : ret;
}
/**
* <p>Find the latest index of any of a set of potential substrings.</p>
*
* <p><code>null</code> string will return <code>-1</code>.</p>
*
* @param str the String to check
* @param searchStrs the Strings to search for
* @return the last index of any of the Strings
* @throws NullPointerException if any of searchStrs[i] is <code>null</code>
*/
public static int lastIndexOfAny(String str, String... searchStrs) {
if ((str == null) || (searchStrs == null)) {
return -1;
}
int ret = -1;
int tmp;
for (String searchStr : searchStrs) {
tmp = str.lastIndexOf(searchStr);
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</code>
* characters from the end of the String.</p>
*
* @param str the String to get the substring from
* @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
*/
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 "";
}
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</code>
* characters from the end of the String.</p>
*
* @param str the String to get the substring from
* @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
*/
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()) {
// check this works.
end = str.length();
}
// if start is greater than end, return ""
if (start > end) {
return "";
}
if (start < 0) {
start = 0;
}
if (end < 0) {
end = 0;
}
return str.substring(start, end);
}
/**
* <p>Gets the leftmost <code>n</code> characters of a String.</p>
*
* <p>If <code>n</code> characters are not available, or the
* String is <code>null</code>, the String will be returned without
* an exception.</p>
*
* @param str the String to get the leftmost characters from
* @param len the length of the required String
* @return the leftmost characters
* @throws IllegalArgumentException if len is less than zero
*/
public static String left(String str, int len) {
if (len < 0) {
throw new IllegalArgumentException("Requested String length " + len + " is less than zero");
}
if ((str == null) || (str.length() <= len)) {
return str;
} else {
return str.substring(0, len);
}
}
/**
* <p>Gets the rightmost <code>n</code> characters of a String.</p>
*
* <p>If <code>n</code> characters are not available, or the String
* is <code>null</code>, the String will be returned without an
* exception.</p>
*
* @param str the String to get the rightmost characters from
* @param len the length of the required String
* @return the leftmost characters
* @throws IllegalArgumentException if len is less than zero
*/
public static String right(String str, int len) {
if (len < 0) {
throw new IllegalArgumentException("Requested String length " + len + " is less than zero");
}
if ((str == null) || (str.length() <= len)) {
return str;
} else {
return str.substring(str.length() - len);
}
}
/**
* <p>Gets <code>n</code> characters from the middle of a String.</p>
*
* <p>If <code>n</code> characters are not available, the remainder
* of the String will be returned without an exception. If the
* String is <code>null</code>, <code>null</code> will be returned.</p>
*
* @param str the String to get the characters from
* @param pos the position to start from
* @param len the length of the required String
* @return the leftmost characters
* @throws IndexOutOfBoundsException if pos is out of bounds
* @throws IllegalArgumentException if len is less than zero
*/
public static String mid(String str, int pos, int len) {
if ((pos < 0) || ((str != null) && (pos > str.length()))) {
throw new StringIndexOutOfBoundsException("String index " + pos + " is out of bounds");
}
if (len < 0) {
throw new IllegalArgumentException("Requested String length " + len + " is less than zero");
}
if (str == null) {
return null;
}
if (str.length() <= (pos + len)) {
return str.substring(pos);
} else {
return str.substring(pos, pos + len);
}
}
// Splitting
// --------------------------------------------------------------------------
/**
* <p>Splits the provided text into a array, using whitespace as the
* separator.</p>
*
* <p>The separator is not included in the returned String array.</p>
*
* @param str the String to parse
* @return an array of parsed Strings
*/
@Nonnull
public static String[] split(@Nonnull String str) {
return split(str, null, -1);
}
/**
* @param text the text to be split
* @param separator the separator at which the text will be split
* @return the resulting array
* @see #split(String, String, int)
*/
@Nonnull
public static String[] split(@Nonnull String text, @Nullable String separator) {
return split(text, separator, -1);
}
/**
* <p>Splits the provided text into a array, based on a given separator.</p>
*
* <p>The separator is not included in the returned String array. The
* maximum number of splits to perform can be controlled. A <code>null</code>
* separator causes splitting on whitespace.</p>
*
* <p>This is useful for quickly splitting a String into
* an array of tokens, instead of an enumeration of tokens (as
* <code>StringTokenizer</code> does).</p>
*
* @param str the string to parse
* @param separator Characters used as the delimiters. If
* <code>null</code>, 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
*/
@Nonnull
public static String[] split(@Nonnull String str, @Nullable String separator, int max) {
StringTokenizer tok;
if (separator == null) {
// Null separator means we're using StringTokenizer's default
// delimiter, which comprises all whitespace characters.
tok = new StringTokenizer(str);
} else {
tok = new StringTokenizer(str, separator);
}
int listSize = tok.countTokens();
if ((max > 0) && (listSize > max)) {
listSize = max;
}
String[] list = new String[listSize];
int i = 0;
int lastTokenBegin;
int lastTokenEnd = 0;
while (tok.hasMoreTokens()) {
if ((max > 0) && (i == listSize - 1)) {
// In the situation where we hit the max yet have
// tokens left over in our input, the last list
// element gets all remaining text.
String endToken = tok.nextToken();
lastTokenBegin = str.indexOf(endToken, lastTokenEnd);
list[i] = str.substring(lastTokenBegin);
break;
} else {
list[i] = tok.nextToken();
lastTokenBegin = str.indexOf(list[i], lastTokenEnd);
lastTokenEnd = lastTokenBegin + list[i].length();
}
i++;
}
return list;
}
// Joining
// --------------------------------------------------------------------------
/**
* <p>Concatenates elements of an array into a single String.</p>
*
* <p>The difference from join is that concatenate has no delimiter.</p>
*
* @param array the array of values to concatenate.
* @return the concatenated string.
*/
@Nonnull
public static String concatenate(@Nonnull Object... array) {
return join(array, "");
}
/**
* <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</code> separator is the same as a blank String.</p>
*
* @param array the array of values to join together
* @param separator the separator character to use
* @return the joined String
* @deprecated use <code>java.lang.String.join(</code>) instead
*/
@Deprecated
@Nonnull
public static String join(@Nonnull Object[] array, @Nullable String separator) {
if (separator == null) {
separator = "";
}
int arraySize = array.length;
int bufSize = (arraySize == 0 ? 0 : (array[0].toString().length() + separator.length()) * arraySize);
StringBuilder buf = new StringBuilder(bufSize);
for (int i = 0; i < arraySize; i++) {
if (i > 0) {
buf.append(separator);
}
buf.append(array[i]);
}
return buf.toString();
}
/**
* <p>Joins the elements of the provided <code>Iterator</code> into
* a single String containing the provided elements.</p>
*
* <p>No delimiter is added before or after the list. A
* <code>null</code> separator is the same as a blank String.</p>
*
* @param iterator the <code>Iterator</code> of values to join together
* @param separator the separator character to use
* @return the joined String
* @deprecated use <code>java.lang.String.join(</code>) instead
*/
@Deprecated
@Nonnull
public static String join(@Nonnull Iterator<?> iterator, String separator) {
if (separator == null) {
separator = "";
}
StringBuilder buf = new StringBuilder(256); // Java default is 16, probably too small
while (iterator.hasNext()) {
buf.append(iterator.next());
if (iterator.hasNext()) {
buf.append(separator);
}
}
return buf.toString();
}
// Replacing
// --------------------------------------------------------------------------
/**
* <p>Replace a char with another char inside a larger String, once.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl char to search for
* @param with char to replace with
* @return the text with any replacements processed
* @see #replace(String text, char repl, char with, int max)
*/
public static String replaceOnce(@Nullable String text, char repl, char with) {
return replace(text, repl, with, 1);
}
/**
* <p>Replace all occurrences of a char within a string with another char.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl char to search for
* @param with char to replace with
* @return the text with any replacements processed
* @see #replace(String text, char repl, char with, int max)
*/
public static String replace(@Nullable String text, char repl, char with) {
return replace(text, repl, with, -1);
}
/**
* <p>Replace a char with another char inside a larger String,
* for the first <code>max</code> values of the search char.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl char to search for
* @param with char to replace with
* @param max maximum number of values to replace, or <code>-1</code> if no maximum
* @return the text with any replacements processed
*/
public static String replace(@Nullable String text, char repl, char with, int max) {
return replace(text, String.valueOf(repl), String.valueOf(with), max);
}
/**
* <p>Replace a String with another String inside a larger String, once.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl String to search for
* @param with String to replace with
* @return the text with any replacements processed
* @see #replace(String text, String repl, String with, int max)
*/
public static String replaceOnce(@Nullable String text, @Nullable String repl, @Nullable String with) {
return replace(text, repl, with, 1);
}
/**
* <p>Replace all occurrences of a String within another String.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl String to search for
* @param with String to replace with
* @return the text with any replacements processed
* @see #replace(String text, String repl, String with, int max)
*/
public static String replace(@Nullable String text, @Nullable String repl, @Nullable String with) {
return replace(text, repl, with, -1);
}
/**
* <p>Replace a String with another String inside a larger String,
* for the first <code>max</code> values of the search String.</p>
*
* <p>A <code>null</code> reference passed to this method is a no-op.</p>
*
* @param text text to search and replace in
* @param repl String to search for
* @param with String to replace with
* @param max maximum number of values to replace, or <code>-1</code> if no maximum
* @return the text with any replacements processed
*/
public static String replace(@Nullable String text, @Nullable String repl, @Nullable String with, int max) {
if ((text == null) || (repl == null) || (with == null) || (repl.length() == 0)) {
return text;
}
StringBuilder buf = new StringBuilder(text.length());
int start = 0, end;
while ((end = text.indexOf(repl, start)) != -1) {
buf.append(text, start, end).append(with);
start = end + repl.length();
if (--max == 0) {
break;
}
}
buf.append(text, start, text.length());
return buf.toString();
}
/**
* <p>Overlay a part of a String with another String.</p>
*
* @param text String to do overlaying in
* @param overlay String to overlay
* @param start position to start overlaying at
* @param end position to stop overlaying before
* @return String with overlaid text
* @throws NullPointerException if text or overlay is <code>null</code>
*/
@Nonnull
public static String overlayString(@Nonnull String text, @Nonnull String overlay, int start, int end) {
if (overlay == null) {
throw new NullPointerException("overlay is null");
}
return new StringBuilder(start + overlay.length() + text.length() - end + 1)
.append(text, 0, start)
.append(overlay)
.append(text, end, text.length())
.toString();
}
// Centering
// --------------------------------------------------------------------------
/**
* <p>Center a String in a larger String of size <code>n</code>.</p>
*
* <p>Uses spaces as the value to buffer the String with.
* Equivalent to <code>center(str, size, " ")</code>.</p>
*
* @param str String to center
* @param size int size of new String
* @return String containing centered String
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String center(@Nonnull String str, int size) {
return center(str, size, " ");
}
/**
* <p>Center a String in a larger String of size <code>n</code>.</p>
*
* <p>Uses a supplied String as the value to buffer the String with.</p>
*
* @param str String to center
* @param size int size of new String
* @param delim String to buffer the new String with
* @return String containing centered String
* @throws NullPointerException if str or delim is <code>null</code>
* @throws ArithmeticException if delim is the empty String
*/
@Nonnull
public static String center(@Nonnull String str, int size, @Nonnull String delim) {
int sz = str.length();
int p = size - sz;
if (p < 1) {
return str;
}
str = leftPad(str, sz + p / 2, delim);
str = rightPad(str, size, delim);
return str;
}
// Chomping
// --------------------------------------------------------------------------
/**
* <p>Remove the last newline, and everything after it from a String.</p>
*
* @param str String to chomp the newline from
* @return String without chomped newline
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String chomp(@Nonnull String str) {
return chomp(str, "\n");
}
/**
* <p>Remove the last value of a supplied String, and everything after
* it from a String.</p>
*
* @param str String to chomp from
* @param sep String to chomp
* @return String without chomped ending
* @throws NullPointerException if str or sep is <code>null</code>
*/
@Nonnull
public static String chomp(@Nonnull String str, @Nonnull String sep) {
int idx = str.lastIndexOf(sep);
if (idx != -1) {
return str.substring(0, idx);
} else {
return str;
}
}
/**
* <p>Remove a newline if and only if it is at the end
* of the supplied String.</p>
*
* @param str String to chomp from
* @return String without chomped ending
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String chompLast(@Nonnull String str) {
return chompLast(str, "\n");
}
/**
* <p>Remove a value if and only if the String ends with that value.</p>
*
* @param str String to chomp from
* @param sep String to chomp
* @return String without chomped ending
* @throws NullPointerException if str or sep is <code>null</code>
*/
@Nonnull
public static String chompLast(@Nonnull String str, @Nonnull String sep) {
if (str.length() == 0) {
return str;
}
String sub = str.substring(str.length() - sep.length());
if (sep.equals(sub)) {
return str.substring(0, str.length() - sep.length());
} else {
return str;
}
}
/**
* <p>Remove everything and return the last value of a supplied String, and
* everything after it from a String.</p>
*
* @param str String to chomp from
* @param sep String to chomp
* @return String chomped
* @throws NullPointerException if str or sep is <code>null</code>
*/
@Nonnull
public static String getChomp(@Nonnull String str, @Nonnull String sep) {
int idx = str.lastIndexOf(sep);
if (idx == str.length() - sep.length()) {
return sep;
} else if (idx != -1) {
return str.substring(idx);
} else {
return "";
}
}
/**
* <p>Remove the first value of a supplied String, and everything before it
* from a String.</p>
*
* @param str String to chomp from
* @param sep String to chomp
* @return String without chomped beginning
* @throws NullPointerException if str or sep is <code>null</code>
*/
@Nonnull
public static String prechomp(@Nonnull String str, @Nonnull String sep) {
int idx = str.indexOf(sep);
if (idx != -1) {
return str.substring(idx + sep.length());
} else {
return str;
}
}
/**
* <p>Remove and return everything before the first value of a
* supplied String from another String.</p>
*
* @param str String to chomp from
* @param sep String to chomp
* @return String prechomped
* @throws NullPointerException if str or sep is <code>null</code>
*/
@Nonnull
public static String getPrechomp(@Nonnull String str, @Nonnull String sep) {
int idx = str.indexOf(sep);
if (idx != -1) {
return str.substring(0, idx + sep.length());
} else {
return "";
}
}
// Chopping
// --------------------------------------------------------------------------
/**
* <p>Remove the last character from a String.</p>
*
* <p>If the String ends in <code>\r\n</code>, then remove both
* of them.</p>
*
* @param str String to chop last character from
* @return String without last character
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String chop(@Nonnull String str) {
if ("".equals(str)) {
return "";
}
if (str.length() == 1) {
return "";
}
int lastIdx = str.length() - 1;
String ret = str.substring(0, lastIdx);
char last = str.charAt(lastIdx);
if (last == '\n') {
if (ret.charAt(lastIdx - 1) == '\r') {
return ret.substring(0, lastIdx - 1);
}
}
return ret;
}
/**
* <p>Remove <code>\n</code> from end of a String if it's there.
* If a <code>\r</code> precedes it, then remove that too.</p>
*
* @param str String to chop a newline from
* @return String without newline
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String chopNewline(@Nonnull String str) {
int lastIdx = str.length() - 1;
char last = str.charAt(lastIdx);
if (last == '\n') {
if (str.charAt(lastIdx - 1) == '\r') {
lastIdx--;
}
} else {
lastIdx++;
}
return str.substring(0, lastIdx);
}
// Conversion
// --------------------------------------------------------------------------
// spec 3.10.6
/**
* <p>Escapes any values it finds into their String form.</p>
*
* <p>So a tab becomes the characters <code>'\\'</code> and
* <code>'t'</code>.</p>
*
* @param str String to escape values in
* @return String with escaped values
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String escape(@Nonnull String str) {
// improved with code from cybertiger@cyberiantiger.org
// unicode from him, and defaul for < 32's.
int sz = str.length();
StringBuilder buffer = new StringBuilder(2 * sz);
for (int i = 0; i < sz; i++) {
char ch = str.charAt(i);
// handle unicode
// CHECKSTYLE_OFF: MagicNumber
if (ch > 0xfff) {
buffer.append("\\u").append(Integer.toHexString(ch));
} else if (ch > 0xff) {
buffer.append("\\u0").append(Integer.toHexString(ch));
} else if (ch > 0x7f) {
buffer.append("\\u00").append(Integer.toHexString(ch));
}
// CHECKSTYLE_ON: MagicNumber
else if (ch < 32) {
switch (ch) {
case '\b':
buffer.append('\\');
buffer.append('b');
break;
case '\n':
buffer.append('\\');
buffer.append('n');
break;
case '\t':
buffer.append('\\');
buffer.append('t');
break;
case '\f':
buffer.append('\\');
buffer.append('f');
break;
case '\r':
buffer.append('\\');
buffer.append('r');
break;
default:
if (ch > 0xf) {
buffer.append("\\u00").append(Integer.toHexString(ch));
} else {
buffer.append("\\u000").append(Integer.toHexString(ch));
}
break;
}
} else {
switch (ch) {
case '\'':
buffer.append('\\');
buffer.append('\'');
break;
case '"':
buffer.append('\\');
buffer.append('"');
break;
case '\\':
buffer.append('\\');
buffer.append('\\');
break;
default:
buffer.append(ch);
break;
}
}
}
return buffer.toString();
}
// Padding
// --------------------------------------------------------------------------
/**
* <p>Repeat a String <code>n</code> times to form a
* new string.</p>
*
* @param str String to repeat
* @param repeat number of times to repeat str
* @return String with repeated String
* @throws NegativeArraySizeException if <code>repeat &lt; 0</code>
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String repeat(@Nonnull String str, int repeat) {
StringBuilder buffer = new StringBuilder(repeat * str.length());
for (int i = 0; i < repeat; i++) {
buffer.append(str);
}
return buffer.toString();
}
/**
* <p>Right pad a String with spaces.</p>
*
* <p>The String is padded to the size of <code>n</code>.</p>
*
* @param str String to repeat
* @param size number of times to repeat str
* @return right padded String
* @throws NullPointerException if str is <code>null</code>
*/
@Nonnull
public static String rightPad(@Nonnull String str, int size) {
return rightPad(str, size, " ");
}
/**
* <p>Right pad a String with a specified string.</p>
*
* <p>The String is padded to the size of <code>n</code>.</p>
*
* @param str String to pad out
* @param size size to pad to
* @param delim String to pad with
* @return right padded String
* @throws NullPointerException if str or delim is <code>null</code>
* @throws ArithmeticException if delim is the empty String
*/
@Nonnull
public static String rightPad(@Nonnull String str, int size, @Nonnull String delim) {
size = (size - str.length()) / delim.length();
if (size > 0) {
str += repeat(delim, size);
}
return str;
}
/**
* <p>Left pad a String with spaces.</p>
*
* <p>The String is padded to the size of <code>n</code>.</p>
*
* @param str String to pad out
* @param size size to pad to
* @return left padded String
* @throws NullPointerException if str or delim is <code>null</code>
*/
@Nonnull
public static String leftPad(@Nonnull String str, int size) {
return leftPad(str, size, " ");
}
/**
* Left pad a String with a specified string. Pad to a size of n.
*
* @param str String to pad out
* @param size size to pad to
* @param delim String to pad with
* @return left padded String
* @throws NullPointerException if str or delim is null
* @throws ArithmeticException if delim is the empty string
*/
@Nonnull
public static String leftPad(@Nonnull String str, int size, @Nonnull String delim) {
size = (size - str.length()) / delim.length();
if (size > 0) {
str = repeat(delim, size) + str;
}
return str;
}
// Stripping
// --------------------------------------------------------------------------
/**
* <p>Remove whitespace from the front and back of a String.</p>
*
* @param str the String to remove whitespace from
* @return the stripped String
*/
public static String strip(String str) {
return strip(str, null);
}
/**
* <p>Remove a specified String from the front and back of a
* String.</p>
*
* <p>If whitespace is wanted to be removed, used the
* {@link #strip(java.lang.String)} method.</p>
*
* @param str the String to remove a string from
* @param delim the String to remove at start and end
* @return the stripped String
*/
public static String strip(String str, @Nullable String delim) {
str = stripStart(str, delim);
return stripEnd(str, delim);
}
/**
* <p>Strip whitespace from the front and back of every String
* in the array.</p>
*
* @param strs the Strings to remove whitespace from
* @return the stripped Strings
*/
public static String[] stripAll(String... strs) {
return stripAll(strs, null);
}
/**
* <p>Strip the specified delimiter from the front and back of
* every String in the array.</p>
*
* @param strs the Strings to remove a String from
* @param delimiter the String to remove at start and end
* @return the stripped Strings
*/
public static String[] stripAll(String[] strs, @Nullable String delimiter) {
if ((strs == null) || (strs.length == 0)) {
return strs;
}
int sz = strs.length;
String[] newArr = new String[sz];
for (int i = 0; i < sz; i++) {
newArr[i] = strip(strs[i], delimiter);
}
return newArr;
}
/**
* <p>Strip any of a supplied String from the end of a String.</p>
*
* <p>If the strip String is <code>null</code>, whitespace is
* stripped.</p>
*
* @param str the String to remove characters from
* @param strip the String to remove
* @return the stripped String
*/
public static String stripEnd(String str, @Nullable String strip) {
if (str == null) {
return null;
}
int end = str.length();
if (strip == null) {
while ((end != 0) && Character.isWhitespace(str.charAt(end - 1))) {
end--;
}
} else {
while ((end != 0) && (strip.indexOf(str.charAt(end - 1)) != -1)) {
end--;
}
}
return str.substring(0, end);
}
/**
* <p>Strip any of a supplied String from the start of a String.</p>
*
* <p>If the strip String is <code>null</code>, whitespace is
* stripped.</p>
*
* @param str the String to remove characters from
* @param strip the String to remove
* @return the stripped String
*/
public static String stripStart(String str, @Nullable String strip) {
if (str == null) {
return null;
}
int start = 0;
int sz = str.length();
if (strip == null) {
while ((start != sz) && Character.isWhitespace(str.charAt(start))) {
start++;
}
} else {
while ((start != sz) && (strip.indexOf(str.charAt(start)) != -1)) {
start++;
}
}
return str.substring(start);
}
// Case conversion
// --------------------------------------------------------------------------
/**
* <p>Convert a String to upper case, <code>null</code> String
* returns <code>null</code>.</p>
*
* @param str the String to uppercase
* @return the upper cased String
*/
public static String upperCase(String str) {
if (str == null) {
return null;
}
return str.toUpperCase();
}
/**
* <p>Convert a String to lower case, <code>null</code> String
* returns <code>null</code>.</p>
*
* @param str the string to lowercase
* @return the lower cased String
*/
public static String lowerCase(String str) {
if (str == null) {
return null;
}
return str.toLowerCase();
}
/**
* <p>Uncapitalise a String.</p>
*
* <p>That is, convert the first character into lower-case.
* <code>null</code> is returned as <code>null</code>.</p>
*
* @param str the String to uncapitalise
* @return uncapitalised String
*/
public static String uncapitalise(String str) {
if (str == null) {
return null;
} else {
int length = str.length();
if (length == 0) {
return "";
} else {
return new StringBuffer(length)
.append(Character.toLowerCase(str.charAt(0)))
.append(str, 1, length)
.toString();
}
}
}
/**
* <p>Capitalise a String.</p>
*
* <p>That is, convert the first character into title-case.
* <code>null</code> is returned as <code>null</code>.</p>
*
* @param str the String to capitalise
* @return capitalised String
*/
public static String capitalise(String str) {
if (str == null) {
return null;
} else {
int length = str.length();
if (length == 0) {
return "";
} else {
return new StringBuilder(length)
.append(Character.toTitleCase(str.charAt(0)))
.append(str, 1, length)
.toString();
}
}
}
/**
* <p>Swaps the case of String.</p>
*
* <p>Properly looks after making sure the start of words
* are Titlecase and not Uppercase.</p>
*
* <p><code>null</code> is returned as <code>null</code>.</p>
*
* @param str the String to swap the case of
* @return the modified String
*/
public static String swapCase(String str) {
if (str == null) {
return null;
}
int sz = str.length();
StringBuilder buffer = new StringBuilder(sz);
boolean whitespace = false;
char ch;
char tmp;
for (int i = 0; i < sz; i++) {
ch = str.charAt(i);
if (Character.isUpperCase(ch)) {
tmp = Character.toLowerCase(ch);
} else if (Character.isTitleCase(ch)) {
tmp = Character.toLowerCase(ch);
} else if (Character.isLowerCase(ch)) {
if (whitespace) {
tmp = Character.toTitleCase(ch);
} else {
tmp = Character.toUpperCase(ch);
}
} else {
tmp = ch;
}
buffer.append(tmp);
whitespace = Character.isWhitespace(ch);
}
return buffer.toString();
}
/**
* <p>Capitalise all the words in a String.</p>
*
* <p>Uses {@link Character#isWhitespace(char)} as a
* separator between words.</p>
*
* <p><code>null</code> will return <code>null</code>.</p>
*
* @param str the String to capitalise
* @return capitalised String
*/
public static String capitaliseAllWords(String str) {
if (str == null) {
return null;
}
int sz = str.length();
StringBuilder buffer = new StringBuilder(sz);
boolean space = true;
for (int i = 0; i < sz; i++) {
char ch = str.charAt(i);
if (Character.isWhitespace(ch)) {
buffer.append(ch);
space = true;
} else if (space) {
buffer.append(Character.toTitleCase(ch));
space = false;
} else {
buffer.append(ch);
}
}
return buffer.toString();
}
/**
* <p>Uncapitalise all the words in a string.</p>
*
* <p>Uses {@link Character#isWhitespace(char)} as a
* separator between words.</p>
*
* <p><code>null</code> will return <code>null</code>.</p>
*
* @param str the string to uncapitalise
* @return uncapitalised string
*/
public static String uncapitaliseAllWords(String str) {
if (str == null) {
return null;
}
int sz = str.length();
StringBuilder buffer = new StringBuilder(sz);
boolean space = true;
for (int i = 0; i < sz; i++) {
char ch = str.charAt(i);
if (Character.isWhitespace(ch)) {
buffer.append(ch);
space = true;
} else if (space) {
buffer.append(Character.toLowerCase(ch));
space = false;
} else {
buffer.append(ch);
}
}
return buffer.toString();
}
// Nested extraction
// --------------------------------------------------------------------------
/**
* <p>Get the String that is nested in between two instances of the
* same String.</p>
*
* <p>If <code>str</code> is <code>null</code>, will
* return <code>null</code>.</p>
*
* @param str the String containing nested-string
* @param tag the String before and after nested-string
* @return the String that was nested, or <code>null</code>
* @throws NullPointerException if tag is <code>null</code>
*/
public static String getNestedString(String str, @Nonnull String tag) {
return getNestedString(str, tag, tag);
}
/**
* <p>Get the String that is nested in between two Strings.</p>
*
* @param str the String containing nested-string
* @param open the String before nested-string
* @param close the String after nested-string
* @return the String that was nested, or <code>null</code>
* @throws NullPointerException if open or close is <code>null</code>
*/
public static String getNestedString(String str, @Nonnull String open, @Nonnull String close) {
if (str == null) {
return null;
}
int start = str.indexOf(open);
if (start != -1) {
int end = str.indexOf(close, start + open.length());
if (end != -1) {
return str.substring(start + open.length(), end);
}
}
return null;
}
/**
* <p>How many times is the substring in the larger String.</p>
*
* <p><code>null</code> returns <code>0</code>.</p>
*
* @param str the String to check
* @param sub the substring to count
* @return the number of occurrences, 0 if the String is <code>null</code>
* @throws NullPointerException if sub is <code>null</code>
*/
public static int countMatches(@Nullable String str, @Nonnull String sub) {
if (sub.equals("")) {
return 0;
}
if (str == null) {
return 0;
}
int count = 0;
int idx = 0;
while ((idx = str.indexOf(sub, idx)) != -1) {
count++;
idx += sub.length();
}
return count;
}
// Character Tests
// --------------------------------------------------------------------------
/**
* <p>Checks if the String contains only Unicode letters.</p>
*
* <p><code>null</code> will return <code>false</code>.
* An empty String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains letters, and is non-null
*/
public static boolean isAlpha(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (!Character.isLetter(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* <p>Checks if the String contains only whitespace.</p>
*
* <p><code>null</code> will return <code>false</code>. An
* empty String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains whitespace, and is non-null
*/
public static boolean isWhitespace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((!Character.isWhitespace(str.charAt(i)))) {
return false;
}
}
return true;
}
/**
* <p>Checks if the String contains only Unicode letters and
* space (<code>' '</code>).</p>
*
* <p><code>null</code> will return <code>false</code>. An
* empty String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains letters and space,
* and is non-null
*/
public static boolean isAlphaSpace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((!Character.isLetter(str.charAt(i))) && (str.charAt(i) != ' ')) {
return false;
}
}
return true;
}
/**
* <p>Checks if the String contains only Unicode letters or digits.</p>
*
* <p><code>null</code> will return <code>false</code>. An empty
* String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains letters or digits,
* and is non-null
*/
public static boolean isAlphanumeric(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (!Character.isLetterOrDigit(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* <p>Checks if the String contains only Unicode letters, digits
* or space (<code>' '</code>).</p>
*
* <p><code>null</code> will return <code>false</code>. An empty
* String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains letters, digits or space,
* and is non-null
*/
public static boolean isAlphanumericSpace(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if ((!Character.isLetterOrDigit(str.charAt(i))) && (str.charAt(i) != ' ')) {
return false;
}
}
return true;
}
/**
* <p>Checks if the String contains only Unicode digits.</p>
*
* <p><code>null</code> will return <code>false</code>.
* An empty String will return <code>true</code>.</p>
*
* @param str the String to check
* @return <code>true</code> if only contains digits, and is non-null
*/
public static boolean isNumeric(String str) {
if (str == null) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (!Character.isDigit(str.charAt(i))) {
return false;
}
}
return true;
}
// Defaults
// --------------------------------------------------------------------------
/**
* <p>Returns either the passed in <code>Object</code> as a String,
* or, if the <code>Object</code> is <code>null</code>, an empty
* String.</p>
*
* @param obj the Object to check
* @return the passed in Object's toString, or blank if it was
* <code>null</code>
* @deprecated use {@code java.lang.Objects.toString()}
*/
@Deprecated
@Nonnull
public static String defaultString(Object obj) {
return defaultString(obj, "");
}
/**
* <p>Returns either the passed in <code>Object</code> as a String,
* or, if the <code>Object</code> is <code>null</code>, a passed
* in default String.</p>
*
* @param obj the Object to check
* @param defaultString the default String to return if str is
* <code>null</code>
* @return the passed in string, or the default if it was
* <code>null</code>
* @deprecated use {@code java.lang.Objects.toString()}
*/
@Deprecated
@Nonnull
public static String defaultString(Object obj, @Nonnull String defaultString) {
return (obj == null) ? defaultString : obj.toString();
}
// Reversing
// --------------------------------------------------------------------------
/**
* <p>Reverse a String.</p>
*
* <p><code>null</code> String returns <code>null</code>.</p>
*
* @param str the String to reverse
* @return the reversed String
*/
public static String reverse(String str) {
if (str == null) {
return null;
}
return new StringBuffer(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>'.'</code>).</p>
*
* @param str the String to reverse
* @param delimiter the delimiter to use
* @return the reversed String
*/
@Nonnull
public static String reverseDelimitedString(@Nonnull String str, String delimiter) {
// could implement manually, but simple way is to reuse other,
// probably slower, methods.
String[] strs = split(str, delimiter);
reverseArray(strs);
return join(strs, delimiter);
}
/**
* <p>Reverses an array.</p>
*
* @param array the array to reverse
*/
private static void reverseArray(@Nonnull String... array) {
int i = 0;
int j = array.length - 1;
String tmp;
while (j > i) {
tmp = array[j];
array[j] = array[i];
array[i] = tmp;
j--;
i++;
}
}
// Abbreviating
// --------------------------------------------------------------------------
/**
* <p>Turn "Now is the time for all good men" into "Now is the time for..."</p>
* <p>Specifically:</p>
* <p>If str is less than max characters long, return it.
* Else abbreviate it to (substring(str, 0, max-3) + "...").
* If maxWidth is less than 3, throw an IllegalArgumentException.
* In no case will it return a string of length greater than maxWidth.</p>
*
* @param s The string to be abbreviated.
* @param maxWidth maximum length of result string
* @return The abbreviated string.
*/
@Nonnull
public static String abbreviate(@Nonnull String s, int maxWidth) {
return abbreviate(s, 0, maxWidth);
}
/**
* Turn "Now is the time for all good men" into "...is the time for..."
* <p>
* Works like 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.
* In no case will it return a string of length greater than maxWidth.
* </p>
*
* @param s String to abbreviate.
* @param offset left edge of source string
* @param maxWidth maximum length of result string
* @return The abbreviated string.
*/
@Nonnull
public static String abbreviate(@Nonnull String s, int offset, int maxWidth) {
if (maxWidth < 4) {
throw new IllegalArgumentException("Minimum abbreviation width is 4");
}
if (s.length() <= maxWidth) {
return s;
}
if (offset > s.length()) {
offset = s.length();
}
if ((s.length() - offset) < (maxWidth - 3)) {
offset = s.length() - (maxWidth - 3);
}
if (offset <= 4) {
return s.substring(0, maxWidth - 3) + "...";
}
if (maxWidth < 7) {
throw new IllegalArgumentException("Minimum abbreviation width with offset is 7");
}
if ((offset + (maxWidth - 3)) < s.length()) {
return "..." + abbreviate(s.substring(offset), maxWidth - 3);
}
return "..." + s.substring(s.length() - (maxWidth - 3));
}
// Difference
// --------------------------------------------------------------------------
/**
* Compare two strings, and return the portion where they differ.
* (More precisely, return the remainder of the second string,
* starting from where it's different from the first.)
* <p>
* E.g. strdiff("i am a machine", "i am a robot") &rarr; "robot"
* </p>
*
* @param s1 The first string.
* @param s2 The second string.
* @return the portion of s2 where it differs from s1; returns the empty string ("") if they are equal
*/
public static String difference(@Nonnull String s1, @Nonnull String s2) {
int at = differenceAt(s1, s2);
if (at == -1) {
return "";
}
return s2.substring(at);
}
/**
* Compare two strings, and return the index at which the strings begin to differ.
* <p>
* E.g. strdiff("i am a machine", "i am a robot") &rarr; 7
* </p>
*
* @param s1 The first string.
* @param s2 The second string.
* @return the index where s2 and s1 begin to differ; -1 if they are equal
*/
public static int differenceAt(@Nonnull String s1, @Nonnull String s2) {
int i;
for (i = 0; (i < s1.length()) && (i < s2.length()); ++i) {
if (s1.charAt(i) != s2.charAt(i)) {
break;
}
}
if ((i < s2.length()) || (i < s1.length())) {
return i;
}
return -1;
}
/**
* Fill all 'variables' in the given text with the values from the map.
* Any text looking like '${key}' will get replaced by the value stored
* in the namespace map under the 'key'.
*
* @param text The text where replacements will be searched for.
* @param namespace The namespace which contains the replacements.
* @return the interpolated text.
*/
public static String interpolate(String text, @Nonnull Map<?, ?> namespace) {
for (Map.Entry<?, ?> entry : namespace.entrySet()) {
String key = entry.getKey().toString();
Object obj = entry.getValue();
if (obj == null) {
throw new NullPointerException("The value of the key '" + key + "' is null.");
}
String value = obj.toString();
text = replace(text, "${" + key + "}", value);
if (!key.contains(" ")) {
text = replace(text, "$" + key, value);
}
}
return text;
}
/**
* This is basically the inverse of {@link #addAndDeHump(String)}.
* It will remove the 'replaceThis' parameter and uppercase the next
* character afterwards.
* <pre>
* removeAndHump( &quot;this-is-it&quot;, %quot;-&quot; );
* </pre>
* will become 'ThisIsIt'.
*
* @param data The data.
* @param replaceThis The things which should be replaced.
* @return humped String
*/
@Nonnull
public static String removeAndHump(@Nonnull String data, @Nonnull String replaceThis) {
String temp;
StringBuilder out = new StringBuilder();
temp = data;
StringTokenizer st = new StringTokenizer(temp, replaceThis);
while (st.hasMoreTokens()) {
String element = st.nextToken();
out.append(capitalizeFirstLetter(element));
}
return out.toString();
}
/**
* Converts the first character of the given String to uppercase.
* This method does <i>not</i> trim spaces!
*
* @param data the String to get capitalized
* @return data string with the first character transformed to uppercase
* @throws NullPointerException if data is <code>null</code>
* @throws IndexOutOfBoundsException if data is empty
*/
@Nonnull
public static String capitalizeFirstLetter(@Nonnull String data) {
char firstChar = data.charAt(0);
char titleCase = Character.toTitleCase(firstChar);
if (firstChar == titleCase) {
return data;
}
StringBuilder result = new StringBuilder(data.length());
result.append(titleCase);
result.append(data, 1, data.length());
return result.toString();
}
/**
* Converts the first character of the given String to lowercase.
* This method does <i>not</i> trim spaces!
*
* @param data the String to get it's first character lower-cased.
* @return data string with the first character transformed to lowercase
* @throws NullPointerException if data is <code>null</code>
* @throws IndexOutOfBoundsException if data is empty
*/
@Nonnull
public static String lowercaseFirstLetter(@Nonnull String data) {
char firstLetter = Character.toLowerCase(data.substring(0, 1).charAt(0));
String restLetters = data.substring(1);
return firstLetter + restLetters;
}
/**
* <p>Take the input string and un-camel-case it.</p>
* <p>'ThisIsIt' will become 'this-is-it'.</p>
*
* @param view the view
* @return deHumped String
*/
@Nonnull
public static String addAndDeHump(@Nonnull String view) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < view.length(); i++) {
if ((i != 0) && Character.isUpperCase(view.charAt(i))) {
sb.append('-');
}
sb.append(view.charAt(i));
}
return sb.toString().trim().toLowerCase(Locale.ENGLISH);
}
/**
* <p>Quote and escape a String with the given character, handling <code>null</code>.</p>
*
* <pre>
* StringUtils.quoteAndEscape(null, *) = null
* StringUtils.quoteAndEscape("", *) = ""
* StringUtils.quoteAndEscape("abc", '"') = abc
* StringUtils.quoteAndEscape("a\"bc", '"') = "a\"bc"
* StringUtils.quoteAndEscape("a\"bc", '\'') = 'a\"bc'
* </pre>
*
* @param source The source.
* @param quoteChar The quote character.
* @return the String quoted and escaped
* @see #quoteAndEscape(String, char, char[], char[], char, boolean)
* @see #quoteAndEscape(String, char, char[], char[], char, boolean)
*
*/
public static String quoteAndEscape(@Nullable String source, char quoteChar) {
return quoteAndEscape(source, quoteChar, new char[] {quoteChar}, new char[] {' '}, '\\', false);
}
/**
* <p>Quote and escape a String with the given character, handling <code>null</code>.</p>
*
* @param source the source
* @param quoteChar the quote character
* @param quotingTriggers the quoting trigger
* @return the String quoted and escaped
* @see #quoteAndEscape(String, char, char[], char[], char, boolean)
*
*/
public static String quoteAndEscape(@Nullable String source, char quoteChar, @Nonnull char[] quotingTriggers) {
return quoteAndEscape(source, quoteChar, new char[] {quoteChar}, quotingTriggers, '\\', false);
}
/**
* @param source the source
* @param quoteChar the quote character
* @param escapedChars the escaped characters
* @param escapeChar the escape character
* @param force true/false
* @return the String quoted and escaped
* @see #quoteAndEscape(String, char, char[], char[], char, boolean)
*
*/
public static String quoteAndEscape(
@Nullable String source,
char quoteChar,
@Nonnull final char[] escapedChars,
char escapeChar,
boolean force) {
return quoteAndEscape(source, quoteChar, escapedChars, new char[] {' '}, escapeChar, force);
}
/**
* @param source the source
* @param quoteChar the quote character
* @param escapedChars set of characters to escape
* @param quotingTriggers the quoting trigger
* @param escapeChar prefix for escaping a character
* @param force true/false
* @return the String quoted and escaped
*/
public static String quoteAndEscape(
@Nullable String source,
char quoteChar,
@Nonnull final char[] escapedChars,
@Nonnull final char[] quotingTriggers,
char escapeChar,
boolean force) {
if (source == null) {
return null;
}
if (!force
&& source.startsWith(Character.toString(quoteChar))
&& source.endsWith(Character.toString(quoteChar))) {
return source;
}
String escaped = escape(source, escapedChars, escapeChar);
boolean quote = false;
if (force) {
quote = true;
} else if (!escaped.equals(source)) {
quote = true;
} else {
for (char quotingTrigger : quotingTriggers) {
if (escaped.indexOf(quotingTrigger) > -1) {
quote = true;
break;
}
}
}
if (quote) {
return quoteChar + escaped + quoteChar;
}
return escaped;
}
/**
* @param source the source
* @param escapedChars set of characters to escape
* @param escapeChar prefix for escaping a character
* @return the String escaped
*/
public static String escape(@Nullable String source, @Nonnull final char[] escapedChars, char escapeChar) {
if (source == null) {
return null;
}
char[] eqc = new char[escapedChars.length];
System.arraycopy(escapedChars, 0, eqc, 0, escapedChars.length);
Arrays.sort(eqc);
StringBuilder buffer = new StringBuilder(source.length());
for (int i = 0; i < source.length(); i++) {
final char c = source.charAt(i);
int result = Arrays.binarySearch(eqc, c);
if (result > -1) {
buffer.append(escapeChar);
}
buffer.append(c);
}
return buffer.toString();
}
/**
* Remove all duplicate whitespace characters and replace line terminators with a single space.
*
* @param s a not null String
* @return a string with unique whitespace
*
*/
@Nonnull
public static String removeDuplicateWhitespace(@Nonnull String s) {
StringBuilder result = new StringBuilder();
int length = s.length();
boolean isPreviousWhiteSpace = false;
for (int i = 0; i < length; i++) {
char c = s.charAt(i);
boolean thisCharWhiteSpace = Character.isWhitespace(c);
if (!(isPreviousWhiteSpace && thisCharWhiteSpace)) {
result.append(c);
}
isPreviousWhiteSpace = thisCharWhiteSpace;
}
return result.toString();
}
/**
* Parses the given String and replaces all occurrences of
* '\n', '\r', and "\r\n" with the system line separator.
*
* @param s a not null String
* @return a String that contains only System line separators
* @see #unifyLineSeparators(String, String)
* @deprecated this method produces platform dependent code and contributes to
* non-reproducible builds. In the context of Maven, this is almost never what's needed.
* Remove calls to this method and do not replace them. That is, change
* {@code Stringutils.unifyLineSeparators(s)} to simply {@code s}.
*/
@Deprecated
public static String unifyLineSeparators(@Nullable String s) {
return unifyLineSeparators(s, System.getProperty("line.separator"));
}
/**
* Parses the given String and replaces all occurrences of
* '\n', '\r' and '\r\n' with the system line separator.
*
* @param s a not null String
* @param ls the wanted line separator ("\n" on UNIX), if null using the System line separator
* @return a String that contains only System line separators
* @throws IllegalArgumentException if ls is not '\n', '\r', or "\r\n"
*
*/
public static String unifyLineSeparators(@Nullable String s, @Nullable String ls) {
if (s == null) {
return null;
}
if (ls == null) {
ls = System.getProperty("line.separator");
}
if (!(ls.equals("\n") || ls.equals("\r") || ls.equals("\r\n"))) {
throw new IllegalArgumentException("Requested line separator is invalid.");
}
int length = s.length();
StringBuilder buffer = new StringBuilder(length);
for (int i = 0; i < length; i++) {
if (s.charAt(i) == '\r') {
if ((i + 1) < length && s.charAt(i + 1) == '\n') {
i++;
}
buffer.append(ls);
} else if (s.charAt(i) == '\n') {
buffer.append(ls);
} else {
buffer.append(s.charAt(i));
}
}
return buffer.toString();
}
/**
* <p>Checks if String contains a search character, handling <code>null</code>.
* This method uses {@link String#indexOf(int)}.</p>
*
* <p>A <code>null</code> or empty ("") String will return <code>false</code>.</p>
*
* <pre>
* StringUtils.contains(null, *) = false
* StringUtils.contains("", *) = false
* StringUtils.contains("abc", 'a') = true
* StringUtils.contains("abc", 'z') = false
* </pre>
*
* @param str the String to check, may be null
* @param searchChar the character to find
* @return true if the String contains the search character,
* false if not or <code>null</code> string input
*
*/
public static boolean contains(@Nullable String str, char searchChar) {
return !isEmpty(str) && str.indexOf(searchChar) >= 0;
}
/**
* <p>Checks if String contains a search String, handling <code>null</code>.
* This method uses {@link String#indexOf(int)}.</p>
*
* <p>A <code>null</code> String will return <code>false</code>.</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 str the String to check, may be null
* @param searchStr the String to find, may be null
* @return true if the String contains the search String,
* false if not or <code>null</code> string input
*/
public static boolean contains(@Nullable String str, @Nullable String searchStr) {
return !(str == null || searchStr == null) && str.contains(searchStr);
}
/**
* <p>Checks if String ends with a search String, handling <code>null</code>.</p>
* <p>A <code>null</code> String will return <code>false</code>.</p>
*
* <pre>
* StringUtils.endsWithIgnoreCase(null, *) = false
* StringUtils.endsWithIgnoreCase(*, null) = false
* StringUtils.endsWithIgnoreCase("", "") = true
* StringUtils.endsWithIgnoreCase("abc", "") = true
* StringUtils.endsWithIgnoreCase("abc", "C") = true
* StringUtils.endsWithIgnoreCase("abc", "a") = false
* </pre>
*
* @param str the String to check, may be null
* @param searchStr the String to find at end, may be null
* @return true if the String ends with the search String,
* false if not or <code>null</code> string input
*
*/
public static boolean endsWithIgnoreCase(@Nullable String str, @Nullable String searchStr) {
if (str == null || searchStr == null) {
// for consistency with contains
return false;
}
if (str.length() < searchStr.length()) {
return false;
}
return str.regionMatches(true, str.length() - searchStr.length(), searchStr, 0, searchStr.length());
}
}