001/*
002 * (C) Copyright 2012 Nuxeo SA (http://nuxeo.com/) and contributors.
003 *
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the GNU Lesser General Public License
006 * (LGPL) version 2.1 which accompanies this distribution, and is available at
007 * http://www.gnu.org/licenses/lgpl.html
008 *
009 * This library is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * Contributors:
015 *     ataillefer
016 */
017package org.nuxeo.ecm.diff.service.impl;
018
019import java.util.Arrays;
020
021import org.custommonkey.xmlunit.Difference;
022import org.custommonkey.xmlunit.DifferenceConstants;
023import org.custommonkey.xmlunit.DifferenceListener;
024import org.custommonkey.xmlunit.NodeDetail;
025import org.w3c.dom.Node;
026
027/**
028 * Custom DifferenceListener for XMLUnit Diff.
029 * <p>
030 * It ignores what we call "structural" differences, ie.:
031 * <ul>
032 * <li>DOCTYPE related</li>
033 * <li>Namespace URI</li>
034 * <li>Attribute value</li>
035 * <li>Attribute name not found</li>
036 * <li>Element tag name</li>
037 * <li>Child node list sequence</li>
038 * <li>Child node list length</li>
039 * </ul>
040 *
041 * @author <a href="mailto:ataillefer@nuxeo.com">Antoine Taillefer</a>
042 */
043public class IgnoreStructuralDifferenceListener implements DifferenceListener {
044
045    private static final String SCHEMA_ELEMENT = "schema";
046
047    /**
048     * Difference types to be ignored.
049     */
050    private static final int[] IGNORE = new int[] { DifferenceConstants.HAS_DOCTYPE_DECLARATION_ID,
051            DifferenceConstants.DOCTYPE_NAME_ID, DifferenceConstants.DOCTYPE_PUBLIC_ID_ID,
052            DifferenceConstants.DOCTYPE_SYSTEM_ID_ID, DifferenceConstants.NAMESPACE_URI_ID,
053            DifferenceConstants.ATTR_VALUE_ID, DifferenceConstants.ATTR_NAME_NOT_FOUND_ID,
054            DifferenceConstants.ELEMENT_TAG_NAME_ID, DifferenceConstants.CHILD_NODELIST_SEQUENCE_ID,
055            DifferenceConstants.CHILD_NODELIST_LENGTH_ID };
056
057    static {
058        Arrays.sort(IGNORE);
059    }
060
061    /**
062     * Here want to:
063     * <ul>
064     * <li>Take into account all difference types to be ignored.</li>
065     * <li>Not consider an unbalanced schema, ie. a schema that exists for a document but not for the other one, as a
066     * difference.</li>
067     * </ul>
068     */
069    public int differenceFound(Difference difference) {
070
071        boolean unBalancedSchema = false;
072
073        NodeDetail controlNodeDetail = difference.getControlNodeDetail();
074        NodeDetail testNodeDetail = difference.getTestNodeDetail();
075
076        if (controlNodeDetail != null && testNodeDetail != null) {
077
078            Node controlNode = controlNodeDetail.getNode();
079            Node testNode = testNodeDetail.getNode();
080
081            if (controlNode != null && SCHEMA_ELEMENT.equals(controlNode.getNodeName()) && testNode == null) {
082                unBalancedSchema = true;
083            }
084
085            if (!unBalancedSchema && testNode != null && SCHEMA_ELEMENT.equals(testNode.getNodeName())
086                    && controlNode == null) {
087                unBalancedSchema = true;
088            }
089        }
090
091        return (Arrays.binarySearch(IGNORE, difference.getId()) >= 0 || unBalancedSchema) ? RETURN_IGNORE_DIFFERENCE_NODES_IDENTICAL
092                : RETURN_ACCEPT_DIFFERENCE;
093    }
094
095    public void skippedComparison(Node control, Node test) {
096    }
097}