/*
Copyright 2008-2011 Gephi
Authors : Mathieu Bastian <mathieu.bastian@gephi.org>
Website : http://www.gephi.org
This file is part of Gephi.
DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
Copyright 2011 Gephi Consortium. All rights reserved.
The contents of this file are subject to the terms of either the GNU
General Public License Version 3 only ("GPL") or the Common
Development and Distribution License("CDDL") (collectively, the
"License"). You may not use this file except in compliance with the
License. You can obtain a copy of the License at
http://gephi.org/about/legal/license-notice/
or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
specific language governing permissions and limitations under the
License. When distributing the software, include this License Header
Notice in each file and include the License files at
/cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the
License Header, with the fields enclosed by brackets [] replaced by
your own identifying information:
"Portions Copyrighted [year] [name of copyright owner]"
If you wish your version of this file to be governed by only the CDDL
or only the GPL Version 3, indicate your decision by adding
"[Contributor] elects to include this software in this distribution
under the [CDDL or GPL Version 3] license." If you do not indicate a
single choice of license, a recipient has the option to distribute
your version of this file under either the CDDL, the GPL Version 3 or
to extend the choice of license to its licensees as provided above.
However, if you add GPL Version 3 code and therefore, elected the GPL
Version 3 license, then the option applies only if the new code is
made subject to such option by the copyright holder.
Contributor(s):
Portions Copyrighted 2011 Gephi Consortium.
*/
package org.gephi.plugins.example.filter;
import org.gephi.filters.spi.EdgeFilter;
import org.gephi.filters.spi.FilterProperty;
import org.gephi.graph.api.DirectedGraph;
import org.gephi.graph.api.Edge;
import org.gephi.graph.api.Graph;
/**
* Remove mutual edges so a directed graph is transformed to an undirected graph.
* <p>
* This example shows how to implement a simple edge filter. The
* <code>evaluate()</code> method returns <code>false</code> for one of the mutual
* edge so it gets removed. The <code>init()</code> method returns a boolean to
* inform the system if the filter can be applied. It returns <code>false</code>
* here in the case the graph is not a directed graph.
*
* @author Mathieu Bastian
*/
public class TransformToUndirectedFilter implements EdgeFilter {
@Override
public boolean init(Graph graph) {
return graph instanceof DirectedGraph;
}
@Override
public boolean evaluate(Graph graph, Edge edge) {
DirectedGraph directedGraph = (DirectedGraph) graph;
//Make sure the edge is not self loop
if (!edge.isSelfLoop()) {
//Get the potential mutual edge
Edge mutualEdge = directedGraph.getEdge(edge.getTarget(), edge.getSource());
//Remove the mutual edge if exists
//Make sure only one of the two mutual edges will bre removed
if (mutualEdge != null && mutualEdge.getId() < edge.getId()) {
return false;
}
}
return true;
}
@Override
public void finish() {
}
@Override
public String getName() {
return "Transform to Undirected";
}
@Override
public FilterProperty[] getProperties() {
return new FilterProperty[0];
}
}