| /* |
| * 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.lucene.analysis.util; |
| |
| /** |
| * Some commonly-used stemming functions |
| * |
| * @lucene.internal |
| */ |
| public class StemmerUtil { |
| /** no instance */ |
| private StemmerUtil() {} |
| |
| /** |
| * Returns true if the character array starts with the suffix. |
| * |
| * @param s Input Buffer |
| * @param len length of input buffer |
| * @param prefix Prefix string to test |
| * @return true if <code>s</code> starts with <code>prefix</code> |
| */ |
| public static boolean startsWith(char s[], int len, String prefix) { |
| final int prefixLen = prefix.length(); |
| if (prefixLen > len) return false; |
| for (int i = 0; i < prefixLen; i++) if (s[i] != prefix.charAt(i)) return false; |
| return true; |
| } |
| |
| /** |
| * Returns true if the character array ends with the suffix. |
| * |
| * @param s Input Buffer |
| * @param len length of input buffer |
| * @param suffix Suffix string to test |
| * @return true if <code>s</code> ends with <code>suffix</code> |
| */ |
| public static boolean endsWith(char s[], int len, String suffix) { |
| final int suffixLen = suffix.length(); |
| if (suffixLen > len) return false; |
| for (int i = suffixLen - 1; i >= 0; i--) |
| if (s[len - (suffixLen - i)] != suffix.charAt(i)) return false; |
| |
| return true; |
| } |
| |
| /** |
| * Returns true if the character array ends with the suffix. |
| * |
| * @param s Input Buffer |
| * @param len length of input buffer |
| * @param suffix Suffix string to test |
| * @return true if <code>s</code> ends with <code>suffix</code> |
| */ |
| public static boolean endsWith(char s[], int len, char suffix[]) { |
| final int suffixLen = suffix.length; |
| if (suffixLen > len) return false; |
| for (int i = suffixLen - 1; i >= 0; i--) |
| if (s[len - (suffixLen - i)] != suffix[i]) return false; |
| |
| return true; |
| } |
| |
| /** |
| * Delete a character in-place |
| * |
| * @param s Input Buffer |
| * @param pos Position of character to delete |
| * @param len length of input buffer |
| * @return length of input buffer after deletion |
| */ |
| public static int delete(char s[], int pos, int len) { |
| assert pos < len; |
| if (pos < len - 1) { // don't arraycopy if asked to delete last character |
| System.arraycopy(s, pos + 1, s, pos, len - pos - 1); |
| } |
| return len - 1; |
| } |
| |
| /** |
| * Delete n characters in-place |
| * |
| * @param s Input Buffer |
| * @param pos Position of character to delete |
| * @param len Length of input buffer |
| * @param nChars number of characters to delete |
| * @return length of input buffer after deletion |
| */ |
| public static int deleteN(char s[], int pos, int len, int nChars) { |
| assert pos + nChars <= len; |
| if (pos + nChars < len) { // don't arraycopy if asked to delete the last characters |
| System.arraycopy(s, pos + nChars, s, pos, len - pos - nChars); |
| } |
| return len - nChars; |
| } |
| } |