/*
* Copyright 2007 Guy Van den Broeck
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.outerj.daisy.diff.html.ancestor;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.compare.internal.LCSSettings;
import org.eclipse.compare.rangedifferencer.IRangeComparator;
import org.eclipse.compare.rangedifferencer.RangeDifference;
import org.eclipse.compare.rangedifferencer.RangeDifferencer;
import org.outerj.daisy.diff.html.dom.Node;
import org.outerj.daisy.diff.html.dom.TagNode;
import org.outerj.daisy.diff.html.dom.TextNode;
/**
* A comparator that compares only the elements of text inside a given tag.
*/
public class TextOnlyComparator implements IRangeComparator {
private List<TextNode> leafs = new ArrayList<TextNode>();
public TextOnlyComparator(TagNode tree) {
addRecursive(tree);
}
private void addRecursive(TagNode tree) {
for (Node child : tree) {
if (child instanceof TagNode) {
TagNode tagnode = (TagNode) child;
addRecursive(tagnode);
} else if (child instanceof TextNode) {
TextNode textnode = (TextNode) child;
leafs.add(textnode);
}
}
}
public int getRangeCount() {
return leafs.size();
}
public boolean rangesEqual(int owni, IRangeComparator otherComp, int otheri) {
TextOnlyComparator other;
try {
other = (TextOnlyComparator) otherComp;
} catch (ClassCastException e) {
return false;
}
return getLeaf(owni).isSameText(other.getLeaf(otheri));
}
private TextNode getLeaf(int owni) {
return leafs.get(owni);
}
public boolean skipRangeComparison(int arg0, int arg1, IRangeComparator arg2) {
return false;
}
public double getMatchRatio(TextOnlyComparator other) {
LCSSettings settings = new LCSSettings();
settings.setUseGreedyMethod(true);
settings.setPowLimit(1.5);
settings.setTooLong(150 * 150);
RangeDifference[] differences = RangeDifferencer.findDifferences(
settings, other, this);
int distanceOther = 0;
for (RangeDifference d : differences) {
distanceOther += d.leftLength();
}
int distanceThis = 0;
for (RangeDifference d : differences) {
distanceThis += d.rightLength();
}
return ((0.0 + distanceOther) / other.getRangeCount() + (0.0 + distanceThis)
/ getRangeCount()) / 2;
}
}