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Contains interfaces for the portal services. Interfaces are only loaded by the global class loader and are shared by all plugins.

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/**
 * Copyright (c) 2000-2013 Liferay, Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 */

package com.liferay.portal.kernel.util;

/**
 * 

* See http://en.wikipedia.org/wiki/Knuth-Morris-Pratt_algorithm. *

* * @author Shuyang Zhou */ public class KMPSearch { public static int[] generateNexts(byte[] pattern) { int length = pattern.length; int[] nexts = new int[length]; nexts[0] = -1; int i = 0; int j = -1; while (i < (length - 1)) { if ((j == -1) || (pattern[i] == pattern[j])) { i++; j++; nexts[i] = j; } else { j = nexts[j]; } } return nexts; } public static int[] generateNexts(char[] pattern) { int length = pattern.length; int[] nexts = new int[length]; nexts[0] = -1; int i = 0; int j = -1; while (i < (length - 1)) { if ((j == -1) || (pattern[i] == pattern[j])) { i++; j++; nexts[i] = j; } else { j = nexts[j]; } } return nexts; } public static int[] generateNexts(CharSequence pattern) { int length = pattern.length(); int[] nexts = new int[length]; nexts[0] = -1; int i = 0; int j = -1; while (i < (length - 1)) { if ((j == -1) || (pattern.charAt(i) == pattern.charAt(j))) { i++; j++; nexts[i] = j; } else { j = nexts[j]; } } return nexts; } public static int search(byte[] text, byte[] pattern) { int[] nexts = generateNexts(pattern); return search(text, 0, text.length, pattern, nexts); } public static int search(byte[] text, byte[] pattern, int[] nexts) { return search(text, 0, text.length, pattern, nexts); } public static int search( byte[] text, int offset, byte[] pattern, int[] nexts) { return search(text, offset, text.length - offset, pattern, nexts); } public static int search( byte[] text, int offset, int length, byte[] pattern, int[] nexts) { int patternLength = pattern.length; int i = 0; int j = 0; while ((i < length) && (j < patternLength)) { if ((j == -1) || (text[i + offset] == pattern[j])) { i++; j++; } else { j = nexts[j]; } } if (j >= patternLength) { return i - patternLength + offset; } else { return -1; } } public static int search(char[] text, char[] pattern) { int[] nexts = generateNexts(pattern); return search(text, 0, text.length, pattern, nexts); } public static int search(char[] text, char[] pattern, int[] nexts) { return search(text, 0, text.length, pattern, nexts); } public static int search( char[] text, int offset, char[] pattern, int[] nexts) { return search(text, offset, text.length - offset, pattern, nexts); } public static int search( char[] text, int offset, int length, char[] pattern, int[] nexts) { int patternLength = pattern.length; int i = 0; int j = 0; while ((i < length) && (j < patternLength)) { if ((j == -1) || (text[i + offset] == pattern[j])) { i++; j++; } else { j = nexts[j]; } } if (j >= patternLength) { return i - patternLength + offset; } else { return -1; } } public static int search(CharSequence text, CharSequence pattern) { int[] nexts = generateNexts(pattern); return search(text, 0, text.length(), pattern, nexts); } public static int search( CharSequence text, CharSequence pattern, int[] nexts) { return search(text, 0, text.length(), pattern, nexts); } public static int search( CharSequence text, int offset, CharSequence pattern, int[] nexts) { return search(text, offset, text.length() - offset, pattern, nexts); } public static int search( CharSequence text, int offset, int length, CharSequence pattern, int[] nexts) { int patternLength = pattern.length(); int i = 0; int j = 0; while ((i < length) && (j < patternLength)) { if (j == -1) { i++; j++; } else { char c1 = text.charAt(i + offset); char c2 = pattern.charAt(j); if ((c1 == c2) || (c1 == Character.toUpperCase(c2))) { i++; j++; } else { j = nexts[j]; } } } if (j >= patternLength) { return i - patternLength + offset; } else { return -1; } } }




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