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