| /* |
| * Copyright (C) 2014 The Guava Authors |
| * |
| * Licensed 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. |
| */ |
| |
| package com.google.common.graph; |
| |
| import static com.google.common.truth.Truth.assertThat; |
| import static com.google.common.truth.TruthJUnit.assume; |
| import static org.junit.Assert.assertTrue; |
| import static org.junit.Assert.fail; |
| |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.testing.EqualsTester; |
| import java.util.Set; |
| import org.junit.After; |
| import org.junit.Test; |
| |
| /** |
| * Abstract base class for testing undirected {@link Network} implementations defined in this |
| * package. |
| */ |
| public abstract class AbstractStandardUndirectedNetworkTest extends AbstractNetworkTest { |
| private static final EndpointPair<Integer> ENDPOINTS_N1N2 = EndpointPair.ordered(N1, N2); |
| private static final EndpointPair<Integer> ENDPOINTS_N2N1 = EndpointPair.ordered(N2, N1); |
| |
| @After |
| public void validateUndirectedEdges() { |
| for (Integer node : network.nodes()) { |
| new EqualsTester() |
| .addEqualityGroup( |
| network.inEdges(node), network.outEdges(node), network.incidentEdges(node)) |
| .testEquals(); |
| new EqualsTester() |
| .addEqualityGroup( |
| network.predecessors(node), network.successors(node), network.adjacentNodes(node)) |
| .testEquals(); |
| |
| for (Integer adjacentNode : network.adjacentNodes(node)) { |
| assertThat(network.edgesConnecting(node, adjacentNode)) |
| .containsExactlyElementsIn(network.edgesConnecting(adjacentNode, node)); |
| } |
| } |
| } |
| |
| @Override |
| @Test |
| public void nodes_checkReturnedSetMutability() { |
| Set<Integer> nodes = network.nodes(); |
| try { |
| nodes.add(N2); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addNode(N1); |
| assertThat(network.nodes()).containsExactlyElementsIn(nodes); |
| } |
| } |
| |
| @Override |
| @Test |
| public void edges_checkReturnedSetMutability() { |
| Set<String> edges = network.edges(); |
| try { |
| edges.add(E12); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.edges()).containsExactlyElementsIn(edges); |
| } |
| } |
| |
| @Override |
| @Test |
| public void incidentEdges_checkReturnedSetMutability() { |
| addNode(N1); |
| Set<String> incidentEdges = network.incidentEdges(N1); |
| try { |
| incidentEdges.add(E12); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.incidentEdges(N1)).containsExactlyElementsIn(incidentEdges); |
| } |
| } |
| |
| @Override |
| @Test |
| public void adjacentNodes_checkReturnedSetMutability() { |
| addNode(N1); |
| Set<Integer> adjacentNodes = network.adjacentNodes(N1); |
| try { |
| adjacentNodes.add(N2); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.adjacentNodes(N1)).containsExactlyElementsIn(adjacentNodes); |
| } |
| } |
| |
| @Override |
| public void adjacentEdges_checkReturnedSetMutability() { |
| addEdge(N1, N2, E12); |
| Set<String> adjacentEdges = network.adjacentEdges(E12); |
| try { |
| adjacentEdges.add(E23); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N2, N3, E23); |
| assertThat(network.adjacentEdges(E12)).containsExactlyElementsIn(adjacentEdges); |
| } |
| } |
| |
| @Override |
| @Test |
| public void edgesConnecting_checkReturnedSetMutability() { |
| addNode(N1); |
| addNode(N2); |
| Set<String> edgesConnecting = network.edgesConnecting(N1, N2); |
| try { |
| edgesConnecting.add(E23); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.edgesConnecting(N1, N2)).containsExactlyElementsIn(edgesConnecting); |
| } |
| } |
| |
| @Override |
| @Test |
| public void inEdges_checkReturnedSetMutability() { |
| addNode(N2); |
| Set<String> inEdges = network.inEdges(N2); |
| try { |
| inEdges.add(E12); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.inEdges(N2)).containsExactlyElementsIn(inEdges); |
| } |
| } |
| |
| @Override |
| @Test |
| public void outEdges_checkReturnedSetMutability() { |
| addNode(N1); |
| Set<String> outEdges = network.outEdges(N1); |
| try { |
| outEdges.add(E12); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.outEdges(N1)).containsExactlyElementsIn(outEdges); |
| } |
| } |
| |
| @Override |
| @Test |
| public void predecessors_checkReturnedSetMutability() { |
| addNode(N2); |
| Set<Integer> predecessors = network.predecessors(N2); |
| try { |
| predecessors.add(N1); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.predecessors(N2)).containsExactlyElementsIn(predecessors); |
| } |
| } |
| |
| @Override |
| @Test |
| public void successors_checkReturnedSetMutability() { |
| addNode(N1); |
| Set<Integer> successors = network.successors(N1); |
| try { |
| successors.add(N2); |
| fail(ERROR_MODIFIABLE_COLLECTION); |
| } catch (UnsupportedOperationException e) { |
| addEdge(N1, N2, E12); |
| assertThat(network.successors(N1)).containsExactlyElementsIn(successors); |
| } |
| } |
| |
| @Test |
| public void edges_containsOrderMismatch() { |
| addEdge(N1, N2, E12); |
| assertThat(network.asGraph().edges()).contains(ENDPOINTS_N2N1); |
| assertThat(network.asGraph().edges()).contains(ENDPOINTS_N1N2); |
| } |
| |
| @Test |
| public void edgeConnectingOrNull_orderMismatch() { |
| addEdge(N1, N2, E12); |
| assertThat(network.edgeConnectingOrNull(ENDPOINTS_N2N1)).isEqualTo(E12); |
| assertThat(network.edgeConnectingOrNull(ENDPOINTS_N1N2)).isEqualTo(E12); |
| } |
| |
| @Test |
| public void edgesConnecting_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.edgesConnecting(N1, N2)).containsExactly(E12); |
| assertThat(network.edgesConnecting(N2, N1)).containsExactly(E12); |
| } |
| |
| @Test |
| public void inEdges_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.inEdges(N2)).containsExactly(E12); |
| assertThat(network.inEdges(N1)).containsExactly(E12); |
| } |
| |
| @Test |
| public void outEdges_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.outEdges(N2)).containsExactly(E12); |
| assertThat(network.outEdges(N1)).containsExactly(E12); |
| } |
| |
| @Test |
| public void predecessors_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.predecessors(N2)).containsExactly(N1); |
| assertThat(network.predecessors(N1)).containsExactly(N2); |
| } |
| |
| @Test |
| public void successors_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.successors(N1)).containsExactly(N2); |
| assertThat(network.successors(N2)).containsExactly(N1); |
| } |
| |
| @Test |
| public void inDegree_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.inDegree(N2)).isEqualTo(1); |
| assertThat(network.inDegree(N1)).isEqualTo(1); |
| } |
| |
| @Test |
| public void outDegree_oneEdge() { |
| addEdge(N1, N2, E12); |
| assertThat(network.outDegree(N1)).isEqualTo(1); |
| assertThat(network.outDegree(N2)).isEqualTo(1); |
| } |
| |
| @Test |
| public void edges_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.edges()).containsExactly(E11); |
| } |
| |
| @Test |
| public void incidentEdges_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.incidentEdges(N1)).containsExactly(E11); |
| } |
| |
| @Test |
| public void incidentNodes_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.incidentNodes(E11).nodeU()).isEqualTo(N1); |
| assertThat(network.incidentNodes(E11).nodeV()).isEqualTo(N1); |
| } |
| |
| @Test |
| public void adjacentNodes_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| addEdge(N1, N2, E12); |
| assertThat(network.adjacentNodes(N1)).containsExactly(N1, N2); |
| } |
| |
| @Test |
| public void adjacentEdges_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| addEdge(N1, N2, E12); |
| assertThat(network.adjacentEdges(E11)).containsExactly(E12); |
| } |
| |
| @Test |
| public void edgesConnecting_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11); |
| addEdge(N1, N2, E12); |
| assertThat(network.edgesConnecting(N1, N2)).containsExactly(E12); |
| assertThat(network.edgesConnecting(N2, N1)).containsExactly(E12); |
| assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11); |
| } |
| |
| @Test |
| public void inEdges_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.inEdges(N1)).containsExactly(E11); |
| addEdge(N1, N2, E12); |
| assertThat(network.inEdges(N1)).containsExactly(E11, E12); |
| } |
| |
| @Test |
| public void outEdges_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.outEdges(N1)).containsExactly(E11); |
| addEdge(N2, N1, E12); |
| assertThat(network.outEdges(N1)).containsExactly(E11, E12); |
| } |
| |
| @Test |
| public void predecessors_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.predecessors(N1)).containsExactly(N1); |
| addEdge(N1, N2, E12); |
| assertThat(network.predecessors(N1)).containsExactly(N1, N2); |
| } |
| |
| @Test |
| public void successors_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.successors(N1)).containsExactly(N1); |
| addEdge(N2, N1, E12); |
| assertThat(network.successors(N1)).containsExactly(N1, N2); |
| } |
| |
| @Test |
| public void degree_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.degree(N1)).isEqualTo(2); |
| addEdge(N1, N2, E12); |
| assertThat(network.degree(N1)).isEqualTo(3); |
| } |
| |
| @Test |
| public void inDegree_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.inDegree(N1)).isEqualTo(2); |
| addEdge(N1, N2, E12); |
| assertThat(network.inDegree(N1)).isEqualTo(3); |
| } |
| |
| @Test |
| public void outDegree_selfLoop() { |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(network.outDegree(N1)).isEqualTo(2); |
| addEdge(N2, N1, E12); |
| assertThat(network.outDegree(N1)).isEqualTo(3); |
| } |
| |
| // Element Mutation |
| |
| @Test |
| public void addEdge_existingNodes() { |
| assume().that(graphIsMutable()).isTrue(); |
| |
| // Adding nodes initially for safety (insulating from possible future |
| // modifications to proxy methods) |
| addNode(N1); |
| addNode(N2); |
| assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isTrue(); |
| assertThat(network.edges()).contains(E12); |
| assertThat(network.edgesConnecting(N1, N2)).containsExactly(E12); |
| assertThat(network.edgesConnecting(N2, N1)).containsExactly(E12); |
| } |
| |
| @Test |
| public void addEdge_existingEdgeBetweenSameNodes() { |
| assume().that(graphIsMutable()).isTrue(); |
| |
| assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isTrue(); |
| ImmutableSet<String> edges = ImmutableSet.copyOf(network.edges()); |
| assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isFalse(); |
| assertThat(network.edges()).containsExactlyElementsIn(edges); |
| assertThat(networkAsMutableNetwork.addEdge(N2, N1, E12)).isFalse(); |
| assertThat(network.edges()).containsExactlyElementsIn(edges); |
| } |
| |
| @Test |
| public void addEdge_existingEdgeBetweenDifferentNodes() { |
| assume().that(graphIsMutable()).isTrue(); |
| |
| addEdge(N1, N2, E12); |
| try { |
| // Edge between totally different nodes |
| networkAsMutableNetwork.addEdge(N4, N5, E12); |
| fail(ERROR_ADDED_EXISTING_EDGE); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_REUSE_EDGE); |
| } |
| } |
| |
| @Test |
| public void addEdge_parallelEdge_notAllowed() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsParallelEdges()).isFalse(); |
| |
| addEdge(N1, N2, E12); |
| try { |
| networkAsMutableNetwork.addEdge(N1, N2, EDGE_NOT_IN_GRAPH); |
| fail(ERROR_ADDED_PARALLEL_EDGE); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_PARALLEL_EDGE); |
| } |
| try { |
| networkAsMutableNetwork.addEdge(N2, N1, EDGE_NOT_IN_GRAPH); |
| fail(ERROR_ADDED_PARALLEL_EDGE); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_PARALLEL_EDGE); |
| } |
| } |
| |
| @Test |
| public void addEdge_parallelEdge_allowsParallelEdges() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsParallelEdges()).isTrue(); |
| |
| assertTrue(networkAsMutableNetwork.addEdge(N1, N2, E12)); |
| assertTrue(networkAsMutableNetwork.addEdge(N2, N1, E21)); |
| assertTrue(networkAsMutableNetwork.addEdge(N1, N2, E12_A)); |
| assertThat(network.edgesConnecting(N1, N2)).containsExactly(E12, E12_A, E21); |
| } |
| |
| @Test |
| public void addEdge_orderMismatch() { |
| assume().that(graphIsMutable()).isTrue(); |
| |
| EndpointPair<Integer> endpoints = EndpointPair.ordered(N1, N2); |
| assertThat(networkAsMutableNetwork.addEdge(endpoints, E12)).isTrue(); |
| } |
| |
| @Test |
| public void addEdge_selfLoop_notAllowed() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isFalse(); |
| |
| try { |
| networkAsMutableNetwork.addEdge(N1, N1, E11); |
| fail(ERROR_ADDED_SELF_LOOP); |
| } catch (IllegalArgumentException e) { |
| assertThat(e).hasMessageThat().contains(ERROR_SELF_LOOP); |
| } |
| } |
| |
| /** |
| * This test checks an implementation dependent feature. It tests that the method {@code addEdge} |
| * will silently add the missing nodes to the graph, then add the edge connecting them. We are not |
| * using the proxy methods here as we want to test {@code addEdge} when the end-points are not |
| * elements of the graph. |
| */ |
| @Test |
| public void addEdge_nodesNotInGraph() { |
| assume().that(graphIsMutable()).isTrue(); |
| |
| networkAsMutableNetwork.addNode(N1); |
| assertTrue(networkAsMutableNetwork.addEdge(N1, N5, E15)); |
| assertTrue(networkAsMutableNetwork.addEdge(N4, N1, E41)); |
| assertTrue(networkAsMutableNetwork.addEdge(N2, N3, E23)); |
| assertThat(network.nodes()).containsExactly(N1, N5, N4, N2, N3); |
| assertThat(network.edges()).containsExactly(E15, E41, E23); |
| assertThat(network.edgesConnecting(N1, N5)).containsExactly(E15); |
| assertThat(network.edgesConnecting(N4, N1)).containsExactly(E41); |
| assertThat(network.edgesConnecting(N2, N3)).containsExactly(E23); |
| assertThat(network.edgesConnecting(N3, N2)).containsExactly(E23); |
| } |
| |
| @Test |
| public void addEdge_selfLoop() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| assertThat(networkAsMutableNetwork.addEdge(N1, N1, E11)).isTrue(); |
| assertThat(network.edges()).contains(E11); |
| assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11); |
| } |
| |
| @Test |
| public void addEdge_existingSelfLoopEdgeBetweenSameNodes() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| ImmutableSet<String> edges = ImmutableSet.copyOf(network.edges()); |
| assertThat(networkAsMutableNetwork.addEdge(N1, N1, E11)).isFalse(); |
| assertThat(network.edges()).containsExactlyElementsIn(edges); |
| } |
| |
| @Test |
| public void addEdge_existingEdgeBetweenDifferentNodes_selfLoops() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| try { |
| networkAsMutableNetwork.addEdge(N1, N2, E11); |
| fail("Reusing an existing self-loop edge to connect different nodes succeeded"); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_REUSE_EDGE); |
| } |
| try { |
| networkAsMutableNetwork.addEdge(N2, N2, E11); |
| fail("Reusing an existing self-loop edge to make a different self-loop edge succeeded"); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_REUSE_EDGE); |
| } |
| addEdge(N1, N2, E12); |
| try { |
| networkAsMutableNetwork.addEdge(N1, N1, E12); |
| fail("Reusing an existing edge to add a self-loop edge between different nodes succeeded"); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_REUSE_EDGE); |
| } |
| } |
| |
| @Test |
| public void addEdge_parallelSelfLoopEdge_notAllowed() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| assume().that(network.allowsParallelEdges()).isFalse(); |
| |
| addEdge(N1, N1, E11); |
| try { |
| networkAsMutableNetwork.addEdge(N1, N1, EDGE_NOT_IN_GRAPH); |
| fail("Adding a parallel self-loop edge succeeded"); |
| } catch (IllegalArgumentException e) { |
| assertThat(e.getMessage()).contains(ERROR_PARALLEL_EDGE); |
| } |
| } |
| |
| @Test |
| public void addEdge_parallelSelfLoopEdge_allowsParallelEdges() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| assume().that(network.allowsParallelEdges()).isTrue(); |
| |
| assertTrue(networkAsMutableNetwork.addEdge(N1, N1, E11)); |
| assertTrue(networkAsMutableNetwork.addEdge(N1, N1, E11_A)); |
| assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11, E11_A); |
| } |
| |
| @Test |
| public void removeNode_existingNodeWithSelfLoopEdge() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addNode(N1); |
| addEdge(N1, N1, E11); |
| assertThat(networkAsMutableNetwork.removeNode(N1)).isTrue(); |
| assertThat(network.nodes()).isEmpty(); |
| assertThat(network.edges()).doesNotContain(E11); |
| } |
| |
| @Test |
| public void removeEdge_existingSelfLoopEdge() { |
| assume().that(graphIsMutable()).isTrue(); |
| assume().that(network.allowsSelfLoops()).isTrue(); |
| |
| addEdge(N1, N1, E11); |
| assertThat(networkAsMutableNetwork.removeEdge(E11)).isTrue(); |
| assertThat(network.edges()).doesNotContain(E11); |
| assertThat(network.edgesConnecting(N1, N1)).isEmpty(); |
| } |
| } |