org.jgrapht.graph.ParanoidGraph Maven / Gradle / Ivy
/* ==========================================
* JGraphT : a free Java graph-theory library
* ==========================================
*
* Project Info: http://jgrapht.sourceforge.net/
* Project Creator: Barak Naveh (http://sourceforge.net/users/barak_naveh)
*
* (C) Copyright 2003-2008, by Barak Naveh and Contributors.
*
* This program and the accompanying materials are dual-licensed under
* either
*
* (a) the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation, or (at your option) any
* later version.
*
* or (per the licensee's choosing)
*
* (b) the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation.
*/
/* -------------------
* ParanoidGraph.java
* -------------------
* (C) Copyright 2007-2008, by John V. Sichi and Contributors.
*
* Original Author: John V. Sichi
* Contributor(s): -
*
* $Id$
*
* Changes
* -------
* 8-Nov-2007 : Initial revision (JVS);
*
*/
package org.jgrapht.graph;
import java.util.*;
import org.jgrapht.*;
/**
* ParanoidGraph provides a way to verify that objects added to a graph obey the
* standard equals/hashCode contract. It can be used to wrap an underlying graph
* to be verified. Note that the verification is very expensive, so
* ParanoidGraph should only be used during debugging.
*
* @author John Sichi
* @version $Id$
*/
public class ParanoidGraph
extends GraphDelegator
{
/**
*/
private static final long serialVersionUID = 5075284167422166539L;
public ParanoidGraph(Graph g)
{
super(g);
}
/**
* @see Graph#addEdge(Object, Object, Object)
*/
@Override public boolean addEdge(V sourceVertex, V targetVertex, E e)
{
verifyAdd(edgeSet(), e);
return super.addEdge(sourceVertex, targetVertex, e);
}
/**
* @see Graph#addVertex(Object)
*/
@Override public boolean addVertex(V v)
{
verifyAdd(vertexSet(), v);
return super.addVertex(v);
}
private static void verifyAdd(Set set, T t)
{
for (T o : set) {
if (o == t) {
continue;
}
if (o.equals(t) && (o.hashCode() != t.hashCode())) {
throw new IllegalArgumentException(
"ParanoidGraph detected objects "
+ "o1 (hashCode=" + o.hashCode()
+ ") and o2 (hashCode=" + t.hashCode()
+ ") where o1.equals(o2) "
+ "but o1.hashCode() != o2.hashCode()");
}
}
}
}
// End ParanoidGraph.java