org.jgrapht.graph.AsUnweightedGraph Maven / Gradle / Ivy
/*
* (C) Copyright 2007-2018, by Lucas J Scharenbroich and Contributors.
*
* JGraphT : a free Java graph-theory library
*
* 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.
*/
package org.jgrapht.graph;
import org.jgrapht.*;
import java.io.*;
/**
* An unweighted view of a graph.
*
*
* An unweighted view of the backing weighted graph specified in the constructor. This graph allows
* modules to apply algorithms designed for unweighted graphs to a weighted graph by simply ignoring
* edge weights. Query operations on this graph "read through" to the backing graph. Vertex
* addition/removal and edge addition/removal are all supported (and immediately reflected in the
* backing graph).
*
*
* Note that edges returned by this graph's accessors are really just the edges of the underlying
* graph.
*
*
* This graph does not pass the hashCode and equals operations through to the backing graph,
* but relies on Object's equals and hashCode methods. This graph will be
* serializable if the backing graph is serializable.
*
* @param the graph vertex type
* @param the graph edge type
*
* @author Lucas J. Scharenbroich
* @since Sep 7, 2007
*/
public class AsUnweightedGraph
extends
GraphDelegator
implements
Serializable
{
private static final long serialVersionUID = 7175505077601824663L;
/**
* Constructor
*
* @param g the backing graph over which an unweighted view is to be created.
*/
public AsUnweightedGraph(Graph g)
{
super(g);
}
/**
* {@inheritDoc}
*/
@Override
public double getEdgeWeight(E e)
{
if (e == null) {
throw new NullPointerException();
} else {
return Graph.DEFAULT_EDGE_WEIGHT;
}
}
/**
* {@inheritDoc}
*/
@Override
public void setEdgeWeight(E e, double weight)
{
throw new UnsupportedOperationException("Graph is unweighted");
}
/**
* {@inheritDoc}
*/
@Override
public GraphType getType()
{
return super.getType().asUnweighted();
}
}
// End AsUnweightedGraph.java