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JGraphT is a free Java graph library
that provides mathematical graph-theory objects and algorithms
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/* ==========================================
* 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 2003-2007, by Barak Naveh and Contributors.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*/
/* -------------------------
* MaskSubgraph.java
* -------------------------
* (C) Copyright 2007-2007, by France Telecom
*
* Original Author: Guillaume Boulmier and Contributors.
*
* $Id: MaskSubgraph.java 568 2007-09-30 00:12:18Z perfecthash $
*
* Changes
* -------
* 05-Jun-2007 : Initial revision (GB);
*
*/
package org.jgrapht.graph;
import java.util.*;
import org.jgrapht.*;
/**
* An unmodifiable subgraph induced by a vertex/edge masking function. The
* subgraph will keep track of edges being added to its vertex subset as well as
* deletion of edges and vertices. When iterating over the vertices/edges, it
* will iterate over the vertices/edges of the base graph and discard
* vertices/edges that are masked (an edge with a masked extremity vertex is
* discarded as well).
*
* @author Guillaume Boulmier
* @since July 5, 2007
*/
public class MaskSubgraph
extends AbstractGraph
{
//~ Static fields/initializers ---------------------------------------------
private static final String UNMODIFIABLE = "this graph is unmodifiable";
//~ Instance fields --------------------------------------------------------
private Graph base;
private Set edges;
private MaskFunctor mask;
private Set vertices;
//~ Constructors -----------------------------------------------------------
/**
* Creates a new induced subgraph. Running-time = O(1).
*
* @param base the base (backing) graph on which the subgraph will be based.
* @param mask vertices and edges to exclude in the subgraph. If a
* vertex/edge is masked, it is as if it is not in the subgraph.
*/
public MaskSubgraph(Graph base, MaskFunctor mask)
{
super();
this.base = base;
this.mask = mask;
this.vertices = new MaskVertexSet(base.vertexSet(), mask);
this.edges = new MaskEdgeSet(base, base.edgeSet(), mask);
}
//~ Methods ----------------------------------------------------------------
/**
* @see Graph#addEdge(Object, Object)
*/
public E addEdge(V sourceVertex, V targetVertex)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
public boolean addEdge(V sourceVertex, V targetVertex, E edge)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#addVertex(Object)
*/
public boolean addVertex(V v)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
public boolean containsEdge(E e)
{
return edgeSet().contains(e);
}
public boolean containsVertex(V v)
{
return !this.mask.isVertexMasked(v) && this.base.containsVertex(v);
}
/**
* @see UndirectedGraph#degreeOf(Object)
*/
public int degreeOf(V vertex)
{
return edgesOf(vertex).size();
}
public Set edgeSet()
{
return this.edges;
}
public Set edgesOf(V vertex)
{
assertVertexExist(vertex);
return new MaskEdgeSet(
this.base,
this.base.edgesOf(vertex),
this.mask);
}
public Set getAllEdges(V sourceVertex, V targetVertex)
{
Set edges = null;
if (containsVertex(sourceVertex) && containsVertex(targetVertex)) {
return new MaskEdgeSet(
this.base,
this.base.getAllEdges(
sourceVertex,
targetVertex),
this.mask);
}
return edges;
}
public E getEdge(V sourceVertex, V targetVertex)
{
Set edges = getAllEdges(sourceVertex, targetVertex);
if ((edges == null) || edges.isEmpty()) {
return null;
} else {
return edges.iterator().next();
}
}
public EdgeFactory getEdgeFactory()
{
return this.base.getEdgeFactory();
}
public V getEdgeSource(E edge)
{
assert (edgeSet().contains(edge));
return this.base.getEdgeSource(edge);
}
public V getEdgeTarget(E edge)
{
assert (edgeSet().contains(edge));
return this.base.getEdgeTarget(edge);
}
public double getEdgeWeight(E edge)
{
assert (edgeSet().contains(edge));
return this.base.getEdgeWeight(edge);
}
/**
* @see DirectedGraph#incomingEdgesOf(Object)
*/
public Set incomingEdgesOf(V vertex)
{
assertVertexExist(vertex);
return new MaskEdgeSet(
this.base,
((DirectedGraph) this.base).incomingEdgesOf(vertex),
this.mask);
}
/**
* @see DirectedGraph#inDegreeOf(Object)
*/
public int inDegreeOf(V vertex)
{
return incomingEdgesOf(vertex).size();
}
/**
* @see DirectedGraph#outDegreeOf(Object)
*/
public int outDegreeOf(V vertex)
{
return outgoingEdgesOf(vertex).size();
}
/**
* @see DirectedGraph#outgoingEdgesOf(Object)
*/
public Set outgoingEdgesOf(V vertex)
{
assertVertexExist(vertex);
return new MaskEdgeSet(
this.base,
((DirectedGraph) this.base).outgoingEdgesOf(vertex),
this.mask);
}
/**
* @see Graph#removeAllEdges(Collection)
*/
public boolean removeAllEdges(Collection edges)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#removeAllEdges(Object, Object)
*/
public Set removeAllEdges(V sourceVertex, V targetVertex)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#removeAllVertices(Collection)
*/
public boolean removeAllVertices(Collection vertices)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#removeEdge(Object)
*/
public boolean removeEdge(E e)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#removeEdge(Object, Object)
*/
public E removeEdge(V sourceVertex, V targetVertex)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
/**
* @see Graph#removeVertex(Object)
*/
public boolean removeVertex(V v)
{
throw new UnsupportedOperationException(UNMODIFIABLE);
}
public Set vertexSet()
{
return this.vertices;
}
}
// End MaskSubgraph.java