1 package org.apache.commons.graph.shortestpath;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.Comparator;
23 import java.util.HashMap;
24
25 import org.apache.commons.graph.Vertex;
26
27 final class ShortestDistances<V extends Vertex>
28 extends HashMap<V, Double>
29 implements Comparator<V>
30 {
31
32 private static final long serialVersionUID = 568538689459177637L;
33
34 /**
35 * {@inheritDoc}
36 */
37 @Override
38 public Double get( Object key )
39 {
40 Double distance = super.get( key );
41 return (distance == null) ? Double.POSITIVE_INFINITY : distance;
42 }
43
44 /**
45 * {@inheritDoc}
46 */
47 public int compare( V left, V right )
48 {
49 return get( left ).compareTo( get( right ) );
50 }
51
52 }