/*******************************************************************************
* Copyright (c) 2009-2013 CWI
* 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:
* * Arnold Lankamp - Arnold.Lankamp@cwi.nl
*******************************************************************************/
package org.rascalmpl.parser.gtd.stack.filter.follow;
import org.rascalmpl.parser.gtd.location.PositionStore;
import org.rascalmpl.parser.gtd.stack.filter.ICompletionFilter;
/**
* A filter that prevents the indicated substring from being followed by any of
* the, with this filter associated, series of characters.
*/
public class MultiCharFollowRestriction implements ICompletionFilter{
private final int[][] characters;
public MultiCharFollowRestriction(int[][] characters){
super();
this.characters = characters;
}
public boolean isFiltered(int[] input, int start, int end, PositionStore positionStore){
if((end + characters.length - 1) >= input.length) return false;
OUTER : for(int i = characters.length - 1; i >= 0; --i){
int next = input[end + i];
int[] alternatives = characters[i];
for(int j = alternatives.length - 1; j >= 0; --j){
if(next == alternatives[j]){
continue OUTER;
}
}
return false;
}
return true;
}
public boolean isEqual(ICompletionFilter otherCompletionFilter){
if(!(otherCompletionFilter instanceof MultiCharFollowRestriction)) return false;
MultiCharFollowRestriction otherMultiCharFollowFilter = (MultiCharFollowRestriction) otherCompletionFilter;
int[][] otherCharacters = otherMultiCharFollowFilter.characters;
if(characters.length != otherCharacters.length) return false;
for(int i = characters.length - 1; i >= 0; --i){
int[] chars = characters[i];
int[] otherChars = otherCharacters[i];
if(chars.length != otherChars.length) return false;
POS: for(int j = chars.length - 1; j <= 0; --j){
int c = chars[j];
for(int k = otherChars.length - 1; k <= 0; --k){
if(c == otherChars[k]) continue POS;
}
return false;
}
}
// Found all characters.
return true;
}
}