/*
* Copyright 2008 Network Engine for Objects in Lund AB [neotechnology.com]
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.neo4j.graphalgo.shortestpath;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import java.util.HashMap;
import java.util.List;
import org.junit.Test;
import org.neo4j.graphalgo.CommonEvaluators;
import org.neo4j.graphalgo.impl.shortestpath.Dijkstra;
import org.neo4j.graphalgo.impl.util.DoubleAdder;
import org.neo4j.graphalgo.impl.util.DoubleComparator;
import org.neo4j.graphdb.Direction;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import common.Neo4jAlgoTestCase;
public class DijkstraIteratorTest extends Neo4jAlgoTestCase
{
@Test
public void testRun()
{
new TestDijkstra().runTest();
}
protected class TestDijkstra extends Dijkstra<Double>
{
public TestDijkstra()
{
super( 0.0, null, null, CommonEvaluators.doubleCostEvaluator( "cost" ),
new DoubleAdder(), new DoubleComparator(), Direction.BOTH,
MyRelTypes.R1 );
}
protected class TestIterator extends Dijkstra<Double>.DijstraIterator
{
public TestIterator( Node startNode,
HashMap<Node,List<Relationship>> predecessors,
HashMap<Node,Double> mySeen, HashMap<Node,Double> otherSeen,
HashMap<Node,Double> myDistances,
HashMap<Node,Double> otherDistances, boolean backwards )
{
super( startNode, predecessors, mySeen, otherSeen, myDistances,
otherDistances, backwards );
}
}
@Test
public void runTest()
{
graph.makeEdge( "start", "a", "cost", (double) 1 );
graph.makeEdge( "a", "x", "cost", (double) 9 );
graph.makeEdge( "a", "b", "cost", (double) 1 );
graph.makeEdge( "b", "x", "cost", (double) 7 );
graph.makeEdge( "b", "c", "cost", (double) 1 );
graph.makeEdge( "c", "x", "cost", (double) 5 );
graph.makeEdge( "c", "d", "cost", (double) 1 );
graph.makeEdge( "d", "x", "cost", (double) 3 );
graph.makeEdge( "d", "e", "cost", (double) 1 );
graph.makeEdge( "e", "x", "cost", (double) 1 );
HashMap<Node,Double> seen1, seen2, dists1, dists2;
seen1 = new HashMap<Node,Double>();
seen2 = new HashMap<Node,Double>();
dists1 = new HashMap<Node,Double>();
dists2 = new HashMap<Node,Double>();
DijstraIterator iter1 = new TestIterator( graph.getNode( "start" ),
predecessors1, seen1, seen2, dists1, dists2, false );
// while ( iter1.hasNext() && !limitReached() && !iter1.isDone() )
assertTrue( iter1.next().equals( graph.getNode( "start" ) ) );
assertTrue( iter1.next().equals( graph.getNode( "a" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 10.0 );
assertTrue( iter1.next().equals( graph.getNode( "b" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 9.0 );
assertTrue( iter1.next().equals( graph.getNode( "c" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 8.0 );
assertTrue( iter1.next().equals( graph.getNode( "d" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 7.0 );
assertTrue( iter1.next().equals( graph.getNode( "e" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 6.0 );
assertTrue( iter1.next().equals( graph.getNode( "x" ) ) );
assertTrue( seen1.get( graph.getNode( "x" ) ) == 6.0 );
assertFalse( iter1.hasNext() );
int count = 0;
// This code below is correct for the alternative priority queue
// while ( iter1.hasNext() )
// {
// iter1.next();
// ++count;
// }
// assertTrue( count == 4 );
// assertTrue( seen1.get( graph.getNode( "x" ) ) == 6.0 );
// Now test node limit
seen1 = new HashMap<Node,Double>();
seen2 = new HashMap<Node,Double>();
dists1 = new HashMap<Node,Double>();
dists2 = new HashMap<Node,Double>();
iter1 = new TestIterator( graph.getNode( "start" ), predecessors1,
seen1, seen2, dists1, dists2, false );
this.numberOfNodesTraversed = 0;
this.limitMaxNodesToTraverse( 3 );
count = 0;
while ( iter1.hasNext() )
{
iter1.next();
++count;
}
assertTrue( count == 3 );
}
}
}