Aaron Kruglikov | 07d8038 | 2015-12-07 16:54:37 -0800 | [diff] [blame] | 1 | package org.onlab.graph; |
| 2 | |
| 3 | import com.google.common.collect.Lists; |
| 4 | import org.junit.Before; |
| 5 | import org.junit.Test; |
| 6 | |
| 7 | import java.util.Iterator; |
| 8 | import java.util.List; |
| 9 | import java.util.Set; |
| 10 | |
| 11 | import static com.google.common.collect.ImmutableSet.of; |
| 12 | import static org.junit.Assert.assertEquals; |
| 13 | import static org.junit.Assert.assertTrue; |
| 14 | |
| 15 | /** |
| 16 | * Class for test KshortestPathsSearch. |
| 17 | */ |
| 18 | public class KShortestPathsSearchTest<V extends Vertex, E extends Edge<V>> extends GraphTest { |
| 19 | private KShortestPathsSearch<TestVertex, TestEdge> kShortestPathsSearch = new KShortestPathsSearch<>(); |
| 20 | private GraphPathSearch.Result<TestVertex, TestEdge> result; |
| 21 | |
| 22 | @Before |
| 23 | public void setUp() { |
| 24 | graph = new AdjacencyListsGraph<>(vertexes(), edges()); |
| 25 | } |
| 26 | @Test |
| 27 | public void noPath() { |
| 28 | graph = new AdjacencyListsGraph<>(of(A, B, C, D), |
| 29 | of(new TestEdge(A, B, 1), |
| 30 | new TestEdge(B, A, 1), |
| 31 | new TestEdge(C, D, 1), |
| 32 | new TestEdge(D, C, 1))); |
| 33 | KShortestPathsSearch<TestVertex, TestEdge> kShortestPathsSearch = new KShortestPathsSearch<>(); |
| 34 | GraphPathSearch.Result<TestVertex, TestEdge> result = kShortestPathsSearch.search(graph, A, D, weight, 1); |
| 35 | Set<Path<TestVertex, TestEdge>> resultPathSet = result.paths(); |
| 36 | assertTrue("There should not be any paths.", resultPathSet.isEmpty()); |
| 37 | } |
| 38 | |
| 39 | @Test |
| 40 | public void testSinglePath() { |
| 41 | //Tests that there is only a single path possible between A and B |
| 42 | graph = new AdjacencyListsGraph<>(vertexes(), edges()); |
| 43 | this.result = kShortestPathsSearch.search(graph, A, B, weight, 2); |
| 44 | Iterator<Path<TestVertex, TestEdge>> itr = result.paths().iterator(); |
| 45 | assertEquals("incorrect paths count", 1, result.paths().size()); |
| 46 | List<TestEdge> correctEdgeList = Lists.newArrayList(); |
| 47 | correctEdgeList.add(new TestEdge(A, B, 1)); |
| 48 | assertTrue("That wrong path was returned.", |
| 49 | edgeListsAreEqual(correctEdgeList, result.paths().iterator().next().edges())); |
| 50 | } |
| 51 | |
| 52 | @Test |
| 53 | public void testTwoPath() { |
| 54 | //Tests that there are only two paths between A and C and that they are returned in the correct order |
| 55 | result = kShortestPathsSearch.search(graph, A, C, weight, 3); |
| 56 | assertTrue("There are an unexpected number of paths.", result.paths().size() == 2); |
| 57 | Iterator<Path<TestVertex, TestEdge>> edgeListIterator = result.paths().iterator(); |
| 58 | List<TestEdge> correctEdgeList = Lists.newArrayList(); |
| 59 | correctEdgeList.add(new TestEdge(A, B, 1)); |
| 60 | correctEdgeList.add(new TestEdge(B, C, 1)); |
| 61 | assertTrue("The first path from A to C was incorrect.", |
| 62 | edgeListsAreEqual(edgeListIterator.next().edges(), correctEdgeList)); |
| 63 | correctEdgeList.clear(); |
| 64 | correctEdgeList.add(new TestEdge(A, C, 3)); |
| 65 | assertTrue("The second path from A to C was incorrect.", |
| 66 | edgeListsAreEqual(edgeListIterator.next().edges(), correctEdgeList)); |
| 67 | } |
| 68 | |
| 69 | @Test |
| 70 | public void testFourPath() { |
| 71 | //Tests that there are only four paths between A and E and that they are returned in the correct order |
| 72 | //Also tests the special case where some correct solutions are equal |
| 73 | result = kShortestPathsSearch.search(graph, A, E, weight, 5); |
| 74 | assertTrue("There are an unexpected number of paths.", result.paths().size() == 4); |
| 75 | Iterator<Path<TestVertex, TestEdge>> edgeListIterator = result.paths().iterator(); |
| 76 | List<TestEdge> correctEdgeList = Lists.newArrayList(); |
| 77 | correctEdgeList.add(new TestEdge(A, B, 1)); |
| 78 | correctEdgeList.add(new TestEdge(B, C, 1)); |
| 79 | correctEdgeList.add(new TestEdge(C, E, 1)); |
| 80 | assertTrue("The first path from A to E was incorrect.", |
| 81 | edgeListsAreEqual(edgeListIterator.next().edges(), correctEdgeList)); |
| 82 | correctEdgeList.clear(); |
| 83 | //There are two paths of equal length that should hold positions two and three |
| 84 | List<TestEdge> alternateCorrectEdgeList = Lists.newArrayList(); |
| 85 | correctEdgeList.add(new TestEdge(A, C, 3)); |
| 86 | correctEdgeList.add(new TestEdge(C, E, 1)); |
| 87 | alternateCorrectEdgeList.add(new TestEdge(A, B, 1)); |
| 88 | alternateCorrectEdgeList.add(new TestEdge(B, D, 2)); |
| 89 | alternateCorrectEdgeList.add(new TestEdge(D, E, 1)); |
| 90 | List<TestEdge> candidateOne = edgeListIterator.next().edges(); |
| 91 | List<TestEdge> candidateTwo = edgeListIterator.next().edges(); |
| 92 | if (candidateOne.size() == 2) { |
| 93 | assertTrue("The second path from A to E was incorrect.", |
| 94 | edgeListsAreEqual(candidateOne, correctEdgeList)); |
| 95 | assertTrue("The third path from A to E was incorrect.", |
| 96 | edgeListsAreEqual(candidateTwo, alternateCorrectEdgeList)); |
| 97 | } else { |
| 98 | assertTrue("The second path from A to E was incorrect.", |
| 99 | edgeListsAreEqual(candidateOne, alternateCorrectEdgeList)); |
| 100 | assertTrue("The third path from A to E was incorrect.", |
| 101 | edgeListsAreEqual(candidateTwo, correctEdgeList)); |
| 102 | } |
| 103 | correctEdgeList.clear(); |
| 104 | correctEdgeList.add(new TestEdge(A, B, 1)); |
| 105 | correctEdgeList.add(new TestEdge(B, E, 4)); |
| 106 | assertTrue("The fourth path rom A to E was incorrect", |
| 107 | edgeListsAreEqual(edgeListIterator.next().edges(), correctEdgeList)); |
| 108 | |
| 109 | } |
| 110 | |
| 111 | @Test |
| 112 | public void testPathsFromSink() { |
| 113 | //H is a sink in this topology, insure there are no paths from it to any other location |
| 114 | for (TestVertex vertex : vertexes()) { |
| 115 | assertTrue("There should be no paths from vertex H to any other node.", |
| 116 | kShortestPathsSearch.search(graph, H, vertex, weight, 1).paths().size() == 0); |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | @Test |
| 121 | public void testLimitPathSetSize() { |
| 122 | //Checks to make sure that no more than K paths are returned |
| 123 | result = kShortestPathsSearch.search(graph, A, E, weight, 3); |
| 124 | assertTrue("There are an unexpected number of paths.", result.paths().size() == 3); |
| 125 | result = kShortestPathsSearch.search(graph, A, G, weight, 1); |
| 126 | assertTrue("There are an unexpected number of paths.", result.paths().size() == 1); |
| 127 | } |
| 128 | |
| 129 | private boolean edgeListsAreEqual(List<TestEdge> edgeListOne, List<TestEdge> edgeListTwo) { |
| 130 | if (edgeListOne.size() != edgeListTwo.size()) { |
| 131 | return false; |
| 132 | } |
| 133 | TestEdge edgeOne; |
| 134 | TestEdge edgeTwo; |
| 135 | for (int i = 0; i < edgeListOne.size(); i++) { |
| 136 | edgeOne = edgeListOne.get(i); |
| 137 | edgeTwo = edgeListTwo.get(i); |
| 138 | if (!edgeOne.equals(edgeTwo)) { |
| 139 | return false; |
| 140 | } |
| 141 | } |
| 142 | return true; |
| 143 | } |
| 144 | } |