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Diffstat (limited to 'libjava/gnu/regexp/RETokenRepeated.java')
| -rw-r--r-- | libjava/gnu/regexp/RETokenRepeated.java | 240 |
1 files changed, 0 insertions, 240 deletions
diff --git a/libjava/gnu/regexp/RETokenRepeated.java b/libjava/gnu/regexp/RETokenRepeated.java deleted file mode 100644 index 3165a6f1654..00000000000 --- a/libjava/gnu/regexp/RETokenRepeated.java +++ /dev/null @@ -1,240 +0,0 @@ -/* gnu/regexp/RETokenRepeated.java - Copyright (C) 1998-2001, 2004 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 gnu.regexp; - -import java.util.Vector; - -final class RETokenRepeated extends REToken { - private REToken token; - private int min,max; - private boolean stingy; - private boolean possessive; - - RETokenRepeated(int subIndex, REToken token, int min, int max) { - super(subIndex); - this.token = token; - this.min = min; - this.max = max; - } - - /** Sets the minimal matching mode to true. */ - void makeStingy() { - stingy = true; - } - - /** Queries if this token has minimal matching enabled. */ - boolean isStingy() { - return stingy; - } - - /** Sets possessive matching mode to true. */ - void makePossessive() { - possessive = true; - } - - /** Queries if this token has possessive matching enabled. */ - boolean isPossessive() { - return possessive; - } - - /** - * The minimum length of a repeated token is the minimum length - * of the token multiplied by the minimum number of times it must - * match. - */ - int getMinimumLength() { - return (min * token.getMinimumLength()); - } - - // We do need to save every possible point, but the number of clone() - // invocations here is really a killer for performance on non-stingy - // repeat operators. I'm open to suggestions... - - // Hypothetical question: can you have a RE that matches 1 times, - // 3 times, 5 times, but not 2 times or 4 times? Does having - // the subexpression back-reference operator allow that? - - boolean match(CharIndexed input, REMatch mymatch) { - // number of times we've matched so far - int numRepeats = 0; - - // Possible positions for the next repeat to match at - REMatch newMatch = mymatch; - REMatch last = null; - REMatch current; - - // Add the '0-repeats' index - // positions.elementAt(z) == position [] in input after <<z>> matches - Vector positions = new Vector(); - positions.addElement(newMatch); - - // Declare variables used in loop - REMatch doables; - REMatch doablesLast; - REMatch recurrent; - - do { - // Check for stingy match for each possibility. - if (stingy && (numRepeats >= min)) { - REMatch result = matchRest(input, newMatch); - if (result != null) { - mymatch.assignFrom(result); - return true; - } - } - - doables = null; - doablesLast = null; - - // try next repeat at all possible positions - for (current = newMatch; current != null; current = current.next) { - recurrent = (REMatch) current.clone(); - if (token.match(input, recurrent)) { - // add all items in current to doables array - if (doables == null) { - doables = recurrent; - doablesLast = recurrent; - } else { - // Order these from longest to shortest - // Start by assuming longest (more repeats) - doablesLast.next = recurrent; - } - // Find new doablesLast - while (doablesLast.next != null) { - doablesLast = doablesLast.next; - } - } - } - // if none of the possibilities worked out, break out of do/while - if (doables == null) break; - - // reassign where the next repeat can match - newMatch = doables; - - // increment how many repeats we've successfully found - ++numRepeats; - - positions.addElement(newMatch); - } while (numRepeats < max); - - // If there aren't enough repeats, then fail - if (numRepeats < min) return false; - - // We're greedy, but ease off until a true match is found - int posIndex = positions.size(); - - // At this point we've either got too many or just the right amount. - // See if this numRepeats works with the rest of the regexp. - REMatch allResults = null; - REMatch allResultsLast = null; - - REMatch results = null; - while (--posIndex >= min) { - newMatch = (REMatch) positions.elementAt(posIndex); - results = matchRest(input, newMatch); - if (results != null) { - if (allResults == null) { - allResults = results; - allResultsLast = results; - } else { - // Order these from longest to shortest - // Start by assuming longest (more repeats) - allResultsLast.next = results; - } - // Find new doablesLast - while (allResultsLast.next != null) { - allResultsLast = allResultsLast.next; - } - } - // else did not match rest of the tokens, try again on smaller sample - // or break out when performing possessive matching - if (possessive) break; - } - if (allResults != null) { - mymatch.assignFrom(allResults); // does this get all? - return true; - } - // If we fall out, no matches. - return false; - } - - private REMatch matchRest(CharIndexed input, final REMatch newMatch) { - REMatch current, single; - REMatch doneIndex = null; - REMatch doneIndexLast = null; - // Test all possible matches for this number of repeats - for (current = newMatch; current != null; current = current.next) { - // clone() separates a single match from the chain - single = (REMatch) current.clone(); - if (next(input, single)) { - // chain results to doneIndex - if (doneIndex == null) { - doneIndex = single; - doneIndexLast = single; - } else { - doneIndexLast.next = single; - } - // Find new doneIndexLast - while (doneIndexLast.next != null) { - doneIndexLast = doneIndexLast.next; - } - } - } - return doneIndex; - } - - void dump(StringBuffer os) { - os.append("(?:"); - token.dumpAll(os); - os.append(')'); - if ((max == Integer.MAX_VALUE) && (min <= 1)) - os.append( (min == 0) ? '*' : '+' ); - else if ((min == 0) && (max == 1)) - os.append('?'); - else { - os.append('{').append(min); - if (max > min) { - os.append(','); - if (max != Integer.MAX_VALUE) os.append(max); - } - os.append('}'); - } - if (stingy) os.append('?'); - } -} |