Java example source code file (ConfigurableSimpleUndirectedGraphTest.java)

This example Java source code file (ConfigurableSimpleUndirectedGraphTest.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

abstractundirectedgraphtest, configurablesimpleundirectedgraphtest, illegalargumentexception, mutablegraph, override, set, test, unsupportedoperationexception, util

The ConfigurableSimpleUndirectedGraphTest.java Java example source code

/*
 * 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 org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

import java.util.Set;

/**
 * Tests for an undirected {@link ConfigurableMutableGraph}, creating a simple undirected graph
 * (parallel and self-loop edges are not allowed).
 */
@RunWith(JUnit4.class)
public class ConfigurableSimpleUndirectedGraphTest extends AbstractUndirectedGraphTest {

  @Override
  public MutableGraph<Integer> createGraph() {
    return GraphBuilder.undirected().allowsSelfLoops(false).build();
  }

  @Override
  @Test
  public void nodes_checkReturnedSetMutability() {
    Set<Integer> nodes = graph.nodes();
    try {
      nodes.add(N2);
      fail(ERROR_MODIFIABLE_SET);
    } catch (UnsupportedOperationException e) {
      addNode(N1);
      assertThat(graph.nodes()).containsExactlyElementsIn(nodes);
    }
  }

  @Override
  @Test
  public void adjacentNodes_checkReturnedSetMutability() {
    addNode(N1);
    Set<Integer> adjacentNodes = graph.adjacentNodes(N1);
    try {
      adjacentNodes.add(N2);
      fail(ERROR_MODIFIABLE_SET);
    } catch (UnsupportedOperationException e) {
      addEdge(N1, N2);
      assertThat(graph.adjacentNodes(N1)).containsExactlyElementsIn(adjacentNodes);
    }
  }

  @Override
  @Test
  public void predecessors_checkReturnedSetMutability() {
    addNode(N2);
    Set<Integer> predecessors = graph.predecessors(N2);
    try {
      predecessors.add(N1);
      fail(ERROR_MODIFIABLE_SET);
    } catch (UnsupportedOperationException e) {
      addEdge(N1, N2);
      assertThat(graph.predecessors(N2)).containsExactlyElementsIn(predecessors);
    }
  }

  @Override
  @Test
  public void successors_checkReturnedSetMutability() {
    addNode(N1);
    Set<Integer> successors = graph.successors(N1);
    try {
      successors.add(N2);
      fail(ERROR_MODIFIABLE_SET);
    } catch (UnsupportedOperationException e) {
      addEdge(N1, N2);
      assertThat(graph.successors(N1)).containsExactlyElementsIn(successors);
    }
  }

  // Element Mutation

  @Test
  public void addEdge_selfLoop() {
    try {
      addEdge(N1, N1);
      fail(ERROR_ADDED_SELF_LOOP);
    } catch (IllegalArgumentException e) {
      assertThat(e.getMessage()).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() {
    graph.addNode(N1);
    assertTrue(graph.addEdge(N1, N5));
    assertTrue(graph.addEdge(N4, N1));
    assertTrue(graph.addEdge(N2, N3));
    assertThat(graph.nodes()).containsExactly(N1, N5, N4, N2, N3).inOrder();
    assertThat(graph.adjacentNodes(N1)).containsExactly(N4, N5);
    assertThat(graph.adjacentNodes(N2)).containsExactly(N3);
    assertThat(graph.adjacentNodes(N3)).containsExactly(N2);
    assertThat(graph.adjacentNodes(N4)).containsExactly(N1);
    assertThat(graph.adjacentNodes(N5)).containsExactly(N1);
  }
}