UnhashableObject.java revision 3c77433663281544363151bf284b0240dfd22a42 
1/*
2 * Copyright (C) 2009 The Guava Authors
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
17package com.google.common.collect.testing;
18
19import com.google.common.annotations.GwtCompatible;
20
21/**
22 * An unhashable object to be used in testing as values in our collections.
23 *
24 * <p>This class is GWT compatible.
25 *
26 * @author Regina O'Dell
27 */
28@GwtCompatible
29public class UnhashableObject implements Comparable<UnhashableObject> {
30  private final int value;
31
32  public UnhashableObject(int value) {
33    this.value = value;
34  }
35
36  @Override public boolean equals(Object object) {
37    if (object instanceof UnhashableObject) {
38      UnhashableObject that = (UnhashableObject) object;
39      return this.value == that.value;
40    }
41    return false;
42  }
43
44  @Override public int hashCode() {
45    throw new UnsupportedOperationException();
46  }
47
48  // needed because otherwise Object.toString() calls hashCode()
49  @Override public String toString() {
50    return "DontHashMe" + value;
51  }
52
53  @Override
54  public int compareTo(UnhashableObject o) {
55    return (this.value < o.value) ? -1 : (this.value > o.value) ? 1 : 0;
56  }
57}
58