diff options
Diffstat (limited to 'bundles/org.eclipse.core.net/src/org/eclipse/net/internal/core/StringMatcher.java')
| -rw-r--r-- | bundles/org.eclipse.core.net/src/org/eclipse/net/internal/core/StringMatcher.java | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/bundles/org.eclipse.core.net/src/org/eclipse/net/internal/core/StringMatcher.java b/bundles/org.eclipse.core.net/src/org/eclipse/net/internal/core/StringMatcher.java new file mode 100644 index 000000000..ce73c450c --- /dev/null +++ b/bundles/org.eclipse.core.net/src/org/eclipse/net/internal/core/StringMatcher.java @@ -0,0 +1,395 @@ +/******************************************************************************* + * Copyright (c) 2007 IBM Corporation and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * IBM Corporation - initial API and implementation + *******************************************************************************/ +package org.eclipse.net.internal.core; + +import java.util.Vector; + +/** + * A string pattern matcher, suppporting * and ? wildcards. + * Note: code copied from org.eclipse.jdt.internal.core.util.StringMatcher on April 3, 2001 + * (version 0.1 - 010901H18 [rename jbl]). + */ +public class StringMatcher { + protected String fPattern; + protected int fLength; // pattern length + protected boolean fIgnoreWildCards; + protected boolean fIgnoreCase; + protected boolean fHasLeadingStar; + protected boolean fHasTrailingStar; + protected String fSegments[]; //the given pattern is split into * separated segments + + /* boundary value beyond which we don't need to search in the text */ + protected int fBound = 0; + + + protected static final char fSingleWildCard = '\u0000'; + + public static class Position { + int start; //inclusive + int end; //exclusive + public Position(int start, int end) { + this.start = start; + this.end = end; + } + public int getStart() { + return start; + } + public int getEnd() { + return end; + } + } + /** + * Find the first occurrence of the pattern between <code>start</code)(inclusive) + * and <code>end</code>(exclusive). + * @param text the String object to search in + * @param start the starting index of the search range, inclusive + * @param end the ending index of the search range, exclusive + * @return an <code>StringMatcher.Position</code> object that keeps the starting + * (inclusive) and ending positions (exclusive) of the first occurrence of the + * pattern in the specified range of the text; return null if not found or subtext + * is empty (start==end). A pair of zeros is returned if pattern is empty string + * Note that for pattern like "*abc*" with leading and trailing stars, position of "abc" + * is returned. For a pattern like"*??*" in text "abcdf", (1,3) is returned + */ + + public StringMatcher.Position find(String text, int start, int end) { + if (fPattern == null|| text == null) + throw new IllegalArgumentException(); + + int tlen = text.length(); + if (start < 0) + start = 0; + if (end > tlen) + end = tlen; + if (end < 0 ||start >= end ) + return null; + if (fLength == 0) + return new Position(start, start); + if (fIgnoreWildCards) { + int x = posIn(text, start, end); + if (x < 0) + return null; + return new Position(x, x+fLength); + } + + int segCount = fSegments.length; + if (segCount == 0)//pattern contains only '*'(s) + return new Position (start, end); + + int curPos = start; + int matchStart = -1; + int i; + for (i = 0; i < segCount && curPos < end; ++i) { + String current = fSegments[i]; + int nextMatch = regExpPosIn(text, curPos, end, current); + if (nextMatch < 0 ) + return null; + if(i == 0) + matchStart = nextMatch; + curPos = nextMatch + current.length(); + } + if (i < segCount) + return null; + return new Position(matchStart, curPos); + } + /** + * StringMatcher constructor takes in a String object that is a simple + * pattern which may contain '*' for 0 and many characters and + * '?' for exactly one character. + * + * Literal '*' and '?' characters must be escaped in the pattern + * e.g., "\*" means literal "*", etc. + * + * Escaping any other character (including the escape character itself), + * just results in that character in the pattern. + * e.g., "\a" means "a" and "\\" means "\" + * + * If invoking the StringMatcher with string literals in Java, don't forget + * escape characters are represented by "\\". + * + * @param aPattern the pattern to match text with + * @param ignoreCase if true, case is ignored + * @param ignoreWildCards if true, wild cards and their escape sequences are ignored + * (everything is taken literally). + */ + public StringMatcher(String aPattern, boolean ignoreCase, boolean ignoreWildCards) { + fIgnoreCase = ignoreCase; + fIgnoreWildCards = ignoreWildCards; + fLength = aPattern.length(); + + /* convert case */ + if (fIgnoreCase) { + fPattern = aPattern.toUpperCase(); + } else { + fPattern = aPattern; + } + + if (fIgnoreWildCards) { + parseNoWildCards(); + } else { + parseWildCards(); + } + } + /** + * Given the starting (inclusive) and the ending (exclusive) poisitions in the + * <code>text</code>, determine if the given substring matches with aPattern + * @return true if the specified portion of the text matches the pattern + * @param text a String object that contains the substring to match + * @param start marks the starting position (inclusive) of the substring + * @param end marks the ending index (exclusive) of the substring + */ + public boolean match(String text, int start, int end) { + if (null == text) + throw new IllegalArgumentException(); + + if (start > end) + return false; + + if (fIgnoreWildCards) + return (end - start == fLength) && fPattern.regionMatches(fIgnoreCase, 0, text, start, fLength); + int segCount= fSegments.length; + if (segCount == 0 && (fHasLeadingStar || fHasTrailingStar)) // pattern contains only '*'(s) + return true; + if (start == end) + return fLength == 0; + if (fLength == 0) + return start == end; + + int tlen= text.length(); + if (start < 0) + start= 0; + if (end > tlen) + end= tlen; + + int tCurPos= start; + int bound= end - fBound; + if ( bound < 0) + return false; + int i=0; + String current= fSegments[i]; + int segLength= current.length(); + + /* process first segment */ + if (!fHasLeadingStar){ + if(!regExpRegionMatches(text, start, current, 0, segLength)) { + return false; + } + ++i; + tCurPos= tCurPos + segLength; + } + if ((fSegments.length == 1) && (!fHasLeadingStar) && (!fHasTrailingStar)) { + // only one segment to match, no wildcards specified + return tCurPos == end; + } + /* process middle segments */ + while (i < segCount) { + current= fSegments[i]; + int currentMatch; + int k= current.indexOf(fSingleWildCard); + if (k < 0) { + currentMatch= textPosIn(text, tCurPos, end, current); + if (currentMatch < 0) + return false; + } else { + currentMatch= regExpPosIn(text, tCurPos, end, current); + if (currentMatch < 0) + return false; + } + tCurPos= currentMatch + current.length(); + i++; + } + + /* process final segment */ + if (!fHasTrailingStar && tCurPos != end) { + int clen= current.length(); + return regExpRegionMatches(text, end - clen, current, 0, clen); + } + return i == segCount ; + } + /** + * match the given <code>text</code> with the pattern + * @return true if matched eitherwise false + * @param text a String object + */ + public boolean match(String text) { + return match(text, 0, text.length()); + } + /** + * This method parses the given pattern into segments seperated by wildcard '*' characters. + * Since wildcards are not being used in this case, the pattern consists of a single segment. + */ + private void parseNoWildCards() { + fSegments = new String[1]; + fSegments[0] = fPattern; + fBound = fLength; + } + /** + * This method parses the given pattern into segments seperated by wildcard '*' characters. + * @param p a String object that is a simple regular expression with '*' and/or '?' + */ + private void parseWildCards() { + if(fPattern.startsWith("*"))//$NON-NLS-1$ + fHasLeadingStar = true; + if(fPattern.endsWith("*")) {//$NON-NLS-1$ + /* make sure it's not an escaped wildcard */ + if (fLength > 1 && fPattern.charAt(fLength - 2) != '\\') { + fHasTrailingStar = true; + } + } + + Vector temp = new Vector(); + + int pos = 0; + StringBuffer buf = new StringBuffer(); + while (pos < fLength) { + char c = fPattern.charAt(pos++); + switch (c) { + case '\\': + if (pos >= fLength) { + buf.append(c); + } else { + char next = fPattern.charAt(pos++); + /* if it's an escape sequence */ + if (next == '*' || next == '?' || next == '\\') { + buf.append(next); + } else { + /* not an escape sequence, just insert literally */ + buf.append(c); + buf.append(next); + } + } + break; + case '*': + if (buf.length() > 0) { + /* new segment */ + temp.addElement(buf.toString()); + fBound += buf.length(); + buf.setLength(0); + } + break; + case '?': + /* append special character representing single match wildcard */ + buf.append(fSingleWildCard); + break; + default: + buf.append(c); + } + } + + /* add last buffer to segment list */ + if (buf.length() > 0) { + temp.addElement(buf.toString()); + fBound += buf.length(); + } + + fSegments = new String[temp.size()]; + temp.copyInto(fSegments); + } + /** + * @param text a string which contains no wildcard + * @param start the starting index in the text for search, inclusive + * @param end the stopping point of search, exclusive + * @return the starting index in the text of the pattern , or -1 if not found + */ + protected int posIn(String text, int start, int end) {//no wild card in pattern + int max = end - fLength; + + if (!fIgnoreCase) { + int i = text.indexOf(fPattern, start); + if (i == -1 || i > max) + return -1; + return i; + } + + for (int i = start; i <= max; ++i) { + if (text.regionMatches(true, i, fPattern, 0, fLength)) + return i; + } + + return -1; + } + /** + * @param text a simple regular expression that may only contain '?'(s) + * @param start the starting index in the text for search, inclusive + * @param end the stopping point of search, exclusive + * @param p a simple regular expression that may contains '?' + * @return the starting index in the text of the pattern , or -1 if not found + */ + protected int regExpPosIn(String text, int start, int end, String p) { + int plen = p.length(); + + int max = end - plen; + for (int i = start; i <= max; ++i) { + if (regExpRegionMatches(text, i, p, 0, plen)) + return i; + } + return -1; + } + + /** + * + * @param text the text + * @param tStart the start + * @param p the pattern + * @param pStart the pattern start + * @param plen the pattern length + * @return whether the region matches + */ + protected boolean regExpRegionMatches(String text, int tStart, String p, int pStart, int plen) { + while (plen-- > 0) { + char tchar = text.charAt(tStart++); + char pchar = p.charAt(pStart++); + + /* process wild cards */ + if (!fIgnoreWildCards) { + /* skip single wild cards */ + if (pchar == fSingleWildCard) { + continue; + } + } + if (pchar == tchar) + continue; + if (fIgnoreCase) { + char tc = Character.toUpperCase(tchar); + if (tc == pchar) + continue; + } + return false; + } + return true; + } + /** + * @param text the string to match + * @param start the starting index in the text for search, inclusive + * @param end the stopping point of search, exclusive + * @param p a string that has no wildcard + * @return the starting index in the text of the pattern , or -1 if not found + */ + protected int textPosIn(String text, int start, int end, String p) { + + int plen = p.length(); + int max = end - plen; + + if (!fIgnoreCase) { + int i = text.indexOf(p, start); + if (i == -1 || i > max) + return -1; + return i; + } + + for (int i = start; i <= max; ++i) { + if (text.regionMatches(true, i, p, 0, plen)) + return i; + } + + return -1; + } +} |