| /* Matcher.java -- Instance of a regular expression applied to a char sequence. |
| Copyright (C) 2002, 2004, 2006 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.util.regex; |
| |
| import gnu.java.util.regex.CharIndexed; |
| import gnu.java.util.regex.RE; |
| import gnu.java.util.regex.REMatch; |
| |
| /** |
| * Instance of a regular expression applied to a char sequence. |
| * |
| * @since 1.4 |
| */ |
| public final class Matcher implements MatchResult |
| { |
| private Pattern pattern; |
| private CharSequence input; |
| // We use CharIndexed as an input object to the getMatch method in order |
| // that /\G/ (the end of the previous match) may work. The information |
| // of the previous match is stored in the CharIndexed object. |
| private CharIndexed inputCharIndexed; |
| private int position; |
| private int appendPosition; |
| private REMatch match; |
| |
| Matcher(Pattern pattern, CharSequence input) |
| { |
| this.pattern = pattern; |
| this.input = input; |
| this.inputCharIndexed = RE.makeCharIndexed(input, 0); |
| } |
| |
| /** |
| * @param sb The target string buffer |
| * @param replacement The replacement string |
| * |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| * @exception IndexOutOfBoundsException If the replacement string refers |
| * to a capturing group that does not exist in the pattern |
| */ |
| public Matcher appendReplacement (StringBuffer sb, String replacement) |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| sb.append(input.subSequence(appendPosition, |
| match.getStartIndex()).toString()); |
| sb.append(RE.getReplacement(replacement, match, |
| RE.REG_REPLACE_USE_BACKSLASHESCAPE)); |
| appendPosition = match.getEndIndex(); |
| return this; |
| } |
| |
| /** |
| * @param sb The target string buffer |
| */ |
| public StringBuffer appendTail (StringBuffer sb) |
| { |
| sb.append(input.subSequence(appendPosition, input.length()).toString()); |
| return sb; |
| } |
| |
| /** |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| */ |
| public int end () |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| return match.getEndIndex(); |
| } |
| |
| /** |
| * @param group The index of a capturing group in this matcher's pattern |
| * |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| * @exception IndexOutOfBoundsException If the replacement string refers |
| * to a capturing group that does not exist in the pattern |
| */ |
| public int end (int group) |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| return match.getEndIndex(group); |
| } |
| |
| public boolean find () |
| { |
| boolean first = (match == null); |
| match = pattern.getRE().getMatch(inputCharIndexed, position); |
| if (match != null) |
| { |
| int endIndex = match.getEndIndex(); |
| // Are we stuck at the same position? |
| if (!first && endIndex == position) |
| { |
| match = null; |
| // Not at the end of the input yet? |
| if (position < input.length() - 1) |
| { |
| position++; |
| return find(position); |
| } |
| else |
| return false; |
| } |
| position = endIndex; |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * @param start The index to start the new pattern matching |
| * |
| * @exception IndexOutOfBoundsException If the replacement string refers |
| * to a capturing group that does not exist in the pattern |
| */ |
| public boolean find (int start) |
| { |
| match = pattern.getRE().getMatch(inputCharIndexed, start); |
| if (match != null) |
| { |
| position = match.getEndIndex(); |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| */ |
| public String group () |
| { |
| assertMatchOp(); |
| return match.toString(); |
| } |
| |
| /** |
| * @param group The index of a capturing group in this matcher's pattern |
| * |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| * @exception IndexOutOfBoundsException If the replacement string refers |
| * to a capturing group that does not exist in the pattern |
| */ |
| public String group (int group) |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| return match.toString(group); |
| } |
| |
| /** |
| * @param replacement The replacement string |
| */ |
| public String replaceFirst (String replacement) |
| { |
| reset(); |
| // Semantics might not quite match |
| return pattern.getRE().substitute(input, replacement, position, |
| RE.REG_REPLACE_USE_BACKSLASHESCAPE); |
| } |
| |
| /** |
| * @param replacement The replacement string |
| */ |
| public String replaceAll (String replacement) |
| { |
| reset(); |
| return pattern.getRE().substituteAll(input, replacement, position, |
| RE.REG_REPLACE_USE_BACKSLASHESCAPE); |
| } |
| |
| public int groupCount () |
| { |
| return pattern.getRE().getNumSubs(); |
| } |
| |
| public boolean lookingAt () |
| { |
| match = pattern.getRE().getMatch(inputCharIndexed, 0); |
| if (match != null) |
| { |
| if (match.getStartIndex() == 0) |
| { |
| position = match.getEndIndex(); |
| return true; |
| } |
| match = null; |
| } |
| return false; |
| } |
| |
| /** |
| * Attempts to match the entire input sequence against the pattern. |
| * |
| * If the match succeeds then more information can be obtained via the |
| * start, end, and group methods. |
| * |
| * @see #start() |
| * @see #end() |
| * @see #group() |
| */ |
| public boolean matches () |
| { |
| match = pattern.getRE().getMatch(inputCharIndexed, 0, RE.REG_TRY_ENTIRE_MATCH); |
| if (match != null) |
| { |
| if (match.getStartIndex() == 0) |
| { |
| position = match.getEndIndex(); |
| if (position == input.length()) |
| return true; |
| } |
| match = null; |
| } |
| return false; |
| } |
| |
| /** |
| * Returns the Pattern that is interpreted by this Matcher |
| */ |
| public Pattern pattern () |
| { |
| return pattern; |
| } |
| |
| public Matcher reset () |
| { |
| position = 0; |
| match = null; |
| return this; |
| } |
| |
| /** |
| * @param input The new input character sequence |
| */ |
| public Matcher reset (CharSequence input) |
| { |
| this.input = input; |
| return reset(); |
| } |
| |
| /** |
| * @returns the index of a capturing group in this matcher's pattern |
| * |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| */ |
| public int start () |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| return match.getStartIndex(); |
| } |
| |
| /** |
| * @param group The index of a capturing group in this matcher's pattern |
| * |
| * @exception IllegalStateException If no match has yet been attempted, |
| * or if the previous match operation failed |
| * @exception IndexOutOfBoundsException If the replacement string refers |
| * to a capturing group that does not exist in the pattern |
| */ |
| public int start (int group) |
| throws IllegalStateException |
| { |
| assertMatchOp(); |
| return match.getStartIndex(group); |
| } |
| |
| private void assertMatchOp() |
| { |
| if (match == null) throw new IllegalStateException(); |
| } |
| } |