Yuta HIGUCHI | e3ebe69 | 2017-04-17 10:00:42 -0700 | [diff] [blame] | 1 | /* |
Brian O'Connor | a09fe5b | 2017-08-03 21:12:30 -0700 | [diff] [blame] | 2 | * Copyright 2017-present Open Networking Foundation |
Yuta HIGUCHI | e3ebe69 | 2017-04-17 10:00:42 -0700 | [diff] [blame] | 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onlab.graph; |
| 17 | |
| 18 | import static com.google.common.collect.ImmutableSet.of; |
| 19 | import static org.hamcrest.Matchers.containsInAnyOrder; |
| 20 | import static org.junit.Assert.*; |
| 21 | |
| 22 | import java.util.ArrayList; |
| 23 | import java.util.List; |
| 24 | import java.util.stream.Collectors; |
| 25 | import java.util.stream.Stream; |
| 26 | |
| 27 | import org.junit.Before; |
| 28 | import org.junit.Test; |
| 29 | |
| 30 | import com.google.common.collect.ImmutableList; |
| 31 | |
| 32 | public class LazyKShortestPathsSearchTest extends GraphTest { |
| 33 | |
| 34 | LazyKShortestPathsSearch<TestVertex, TestEdge> sut; |
| 35 | |
| 36 | @Before |
| 37 | public void setUp() { |
| 38 | sut = new LazyKShortestPathsSearch<>(); |
| 39 | } |
| 40 | |
| 41 | @Test |
| 42 | public void noPath() { |
| 43 | graph = new AdjacencyListsGraph<>(of(A, B, C, D), |
| 44 | of(new TestEdge(A, B), |
| 45 | new TestEdge(B, A), |
| 46 | new TestEdge(C, D), |
| 47 | new TestEdge(D, C))); |
| 48 | Stream<Path<TestVertex, TestEdge>> result = sut.lazyPathSearch(graph, A, D, weigher); |
| 49 | assertEquals("There should not be any paths.", 0, result.count()); |
| 50 | } |
| 51 | |
| 52 | @Test |
| 53 | public void fourPath() { |
| 54 | graph = new AdjacencyListsGraph<>(vertexes(), edges()); |
| 55 | Stream<Path<TestVertex, TestEdge>> result = sut.lazyPathSearch(graph, A, E, weigher); |
| 56 | List<Path<TestVertex, TestEdge>> rList = result.limit(42).collect(Collectors.toList()); |
| 57 | |
| 58 | assertEquals("There are an unexpected number of paths.", 4, rList.size()); |
| 59 | |
| 60 | // The shortest path |
| 61 | List<TestEdge> expectedEdges = new ArrayList<>(); |
| 62 | expectedEdges.add(new TestEdge(A, B, W1)); |
| 63 | expectedEdges.add(new TestEdge(B, C, W1)); |
| 64 | expectedEdges.add(new TestEdge(C, E, W1)); |
| 65 | |
| 66 | assertEquals("The first path from A to E was incorrect.", |
| 67 | expectedEdges, rList.get(0).edges()); |
| 68 | assertEquals(W3, rList.get(0).cost()); |
| 69 | |
| 70 | |
| 71 | // There are two paths of equal cost as next shortest path |
| 72 | expectedEdges.clear(); |
| 73 | expectedEdges.add(new TestEdge(A, C, W3)); |
| 74 | expectedEdges.add(new TestEdge(C, E, W1)); |
| 75 | |
| 76 | List<TestEdge> alternateEdges = new ArrayList<>(); |
| 77 | alternateEdges.add(new TestEdge(A, B, W1)); |
| 78 | alternateEdges.add(new TestEdge(B, D, W2)); |
| 79 | alternateEdges.add(new TestEdge(D, E, W1)); |
| 80 | |
| 81 | assertThat(ImmutableList.of(rList.get(1).edges(), rList.get(2).edges()), |
| 82 | containsInAnyOrder(expectedEdges, alternateEdges)); |
| 83 | assertEquals(W4, rList.get(1).cost()); |
| 84 | assertEquals(W4, rList.get(2).cost()); |
| 85 | |
| 86 | |
| 87 | // last shortest path |
| 88 | expectedEdges.clear(); |
| 89 | expectedEdges.add(new TestEdge(A, B, W1)); |
| 90 | expectedEdges.add(new TestEdge(B, E, W4)); |
| 91 | |
| 92 | assertEquals("The fourth path rom A to E was incorrect", |
| 93 | expectedEdges, rList.get(3).edges()); |
| 94 | assertEquals(W5, rList.get(3).cost()); |
| 95 | } |
| 96 | |
| 97 | } |