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;
18 
19 import com.google.common.annotations.GwtCompatible;
20 import java.io.Serializable;
21 import java.util.Arrays;
22 
23 /**
24  * A class that implements {@code Comparable} without generics, such as those found in libraries
25  * that support Java 1.4 and before. Our library needs to do the bare minimum to accommodate such
26  * types, though their use may still require an explicit type parameter and/or warning suppression.
27  *
28  * @author Kevin Bourrillion
29  */
30 @SuppressWarnings("ComparableType")
31 @GwtCompatible
32 class LegacyComparable implements Comparable, Serializable {
33   static final LegacyComparable X = new LegacyComparable("x");
34   static final LegacyComparable Y = new LegacyComparable("y");
35   static final LegacyComparable Z = new LegacyComparable("z");
36 
37   static final Iterable<LegacyComparable> VALUES_FORWARD = Arrays.asList(X, Y, Z);
38   static final Iterable<LegacyComparable> VALUES_BACKWARD = Arrays.asList(Z, Y, X);
39 
40   private final String value;
41 
LegacyComparable(String value)42   LegacyComparable(String value) {
43     this.value = value;
44   }
45 
46   @Override
compareTo(Object object)47   public int compareTo(Object object) {
48     // This method is spec'd to throw CCE if object is of the wrong type
49     LegacyComparable that = (LegacyComparable) object;
50     return this.value.compareTo(that.value);
51   }
52 
53   @Override
equals(Object object)54   public boolean equals(Object object) {
55     if (object instanceof LegacyComparable) {
56       LegacyComparable that = (LegacyComparable) object;
57       return this.value.equals(that.value);
58     }
59     return false;
60   }
61 
62   @Override
hashCode()63   public int hashCode() {
64     return value.hashCode();
65   }
66 
67   private static final long serialVersionUID = 0;
68 }
69