model/src/test/java/org/apache/commons/graph/model/GraphSerializationTestCase.java

package org.apache.commons.graph.model;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import static junit.framework.Assert.assertEquals;
import static org.apache.commons.graph.Graphs.populate;
import static org.apache.commons.graph.Graphs.synchronize;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import org.apache.commons.graph.Graph;
import org.apache.commons.graph.MutableGraph;
import org.apache.commons.graph.builder.AbstractGraphConnection;
import org.apache.commons.graph.builder.GraphConnection;
import org.apache.commons.graph.math.monoid.primitive.DoubleWeightBaseOperations;
import org.apache.commons.graph.model.labeled.BaseLabeledEdge;
import org.apache.commons.graph.model.labeled.BaseLabeledVertex;
import org.apache.commons.graph.model.labeled.BaseLabeledWeightedEdge;
import org.apache.commons.graph.model.labeled.BaseWeightedEdge;
import org.junit.After;
import org.junit.Test;

/**
 * Provides a simple test case to test the Graph serialization.
 */
public class GraphSerializationTestCase
{

    private final static String FILE_NAME = "target/serialiazedGraph.dat";

    @After
    public void cleanUp()
    {
        File f = new File( FILE_NAME );
        if ( f.exists() )
        {
            f.delete();
        }
    }

    @Test
    public void serializeUndirectedGraph()
        throws Exception
    {
        MutableGraph<BaseLabeledVertex, BaseLabeledEdge> g =
        populate( new UndirectedMutableGraph<BaseLabeledVertex, BaseLabeledEdge>() )
        .withConnections( buildGraphConnections() );

        checkSerialization( g );
    }

    @Test
    public void serializeDirectedGraph()
        throws Exception
    {
        MutableGraph<BaseLabeledVertex, BaseLabeledEdge> g =
        populate( new UndirectedMutableGraph<BaseLabeledVertex, BaseLabeledEdge>() )
        .withConnections( buildGraphConnections() );

        checkSerialization( g );
    }

    @Test
    public void serializeUndirectedWeightdGraph()
        throws Exception
    {
        MutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>> g =
        populate( new UndirectedMutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>>() )
        .withConnections( buildWeightedGraphConnections() );

        checkSerialization( g );
    }

    @Test
    public void serializeDirectedWeightdGraph()
        throws Exception
    {
        MutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>> g =
        populate( new UndirectedMutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>>() )
        .withConnections( buildWeightedGraphConnections() );

        checkSerialization( g );
    }

    @Test
    public void serializeSpanningTree()
        throws Exception
    {
        final MutableSpanningTree<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>, Double> spanningTree =
            new MutableSpanningTree<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>, Double>( new DoubleWeightBaseOperations(),
                                                                                                 new BaseWeightedEdge<Double>() );

        populate( spanningTree ).withConnections( buildWeightedGraphConnections() );

        checkSerialization( spanningTree );
    }

    @Test
    public void serializeSyncronyzedDirectedWeightdGraph()
        throws Exception
    {
        MutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>> g =
        populate( new UndirectedMutableGraph<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>>() )
        .withConnections( buildWeightedGraphConnections() );

        checkSerialization( synchronize( g ) );
    }

    @Test
    public void serializePath()
        throws Exception
    {
        BaseLabeledVertex start = new BaseLabeledVertex( "start" );
        BaseLabeledVertex goal = new BaseLabeledVertex( "goal" );
        BaseLabeledVertex a = new BaseLabeledVertex( "a" );
        BaseLabeledVertex b = new BaseLabeledVertex( "b" );
        BaseLabeledVertex c = new BaseLabeledVertex( "c" );

        InMemoryWeightedPath<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>, Double> g =
            new InMemoryWeightedPath<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>, Double>(
                                                                                                  start,
                                                                                                  goal,
                                                                                                  new DoubleWeightBaseOperations(),
                                                                                                  new BaseWeightedEdge<Double>() );

        g.addConnectionInTail( start, new BaseLabeledWeightedEdge<Double>( "start <-> a", 1.5D ), a );
        g.addConnectionInTail( a, new BaseLabeledWeightedEdge<Double>( "a <-> b", 2D ), b );
        g.addConnectionInTail( b, new BaseLabeledWeightedEdge<Double>( "b <-> c", 3D ), c );
        g.addConnectionInTail( c, new BaseLabeledWeightedEdge<Double>( "c <-> goal", 3D ), goal );

        checkSerialization( g );
    }

    /**
     * @param g
     * @throws FileNotFoundException
     * @throws IOException
     * @throws ClassNotFoundException
     */
    private static void checkSerialization( Graph<BaseLabeledVertex, ? extends Serializable> g )
        throws FileNotFoundException, IOException, ClassNotFoundException
    {
        FileOutputStream fout = new FileOutputStream( FILE_NAME );
        ObjectOutputStream oos = new ObjectOutputStream( fout );
        oos.writeObject( g );
        oos.close();

        FileInputStream fin = new FileInputStream( FILE_NAME );
        ObjectInputStream ois = new ObjectInputStream( fin );
        Object cloned = ois.readObject();
        ois.close();

        assertEquals( g, cloned );
    }

    private static GraphConnection<BaseLabeledVertex, BaseLabeledEdge> buildGraphConnections()
    {
        return new AbstractGraphConnection<BaseLabeledVertex, BaseLabeledEdge>()
        {

            @Override
            public void connect()
            {
                BaseLabeledVertex a = addVertex( new BaseLabeledVertex( "a" ) );
                BaseLabeledVertex b = addVertex( new BaseLabeledVertex( "b" ) );
                BaseLabeledVertex c = addVertex( new BaseLabeledVertex( "c" ) );
                BaseLabeledVertex d = addVertex( new BaseLabeledVertex( "d" ) );

                addEdge( new BaseLabeledEdge( "a -> c" ) ).from( a ).to( c );
                addEdge( new BaseLabeledEdge( "c -> d" ) ).from( c ).to( d );
                addEdge( new BaseLabeledEdge( "d -> b" ) ).from( d ).to( b );
            }

        };
    }

    private static GraphConnection<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>> buildWeightedGraphConnections()
    {
        return new AbstractGraphConnection<BaseLabeledVertex, BaseLabeledWeightedEdge<Double>>()
        {

            @Override
            public void connect()
            {
                BaseLabeledVertex a = addVertex( new BaseLabeledVertex( "a" ) );
                BaseLabeledVertex b = addVertex( new BaseLabeledVertex( "b" ) );
                BaseLabeledVertex c = addVertex( new BaseLabeledVertex( "c" ) );
                BaseLabeledVertex d = addVertex( new BaseLabeledVertex( "d" ) );

                addEdge( new BaseLabeledWeightedEdge<Double>( "a -> c", 1D ) ).from( a ).to( c );
                addEdge( new BaseLabeledWeightedEdge<Double>( "c -> d", 1D ) ).from( c ).to( d );
                addEdge( new BaseLabeledWeightedEdge<Double>( "d -> b", 1D ) ).from( d ).to( b );
            }

        };
    }

}