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Java > Open Source Codes > net > sf > retrotranslator > runtime > java > lang > Enum_


1 /***
2  * Retrotranslator: a Java bytecode transformer that translates Java classes
3  * compiled with JDK 5.0 into classes that can be run on JVM 1.4.
4  *
5  * Copyright (c) 2005 - 2007 Taras Puchko
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  * notice, this list of conditions and the following disclaimer in the
15  * documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the copyright holders nor the names of its
17  * contributors may be used to endorse or promote products derived from
18  * this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
30  * THE POSSIBILITY OF SUCH DAMAGE.
31  */

32 package net.sf.retrotranslator.runtime.java.lang;
33
34 import java.io.*;
35 import java.lang.reflect.Method JavaDoc;
36 import java.security.*;
37 import net.sf.retrotranslator.runtime.impl.WeakIdentityTable;
38
39 /**
40  * @author Taras Puchko
41  */

42 public abstract class Enum_<E extends Enum_<E>> implements Comparable JavaDoc<E>, Serializable {
43
44     private static final WeakIdentityTable<Class JavaDoc, ConstantContainer> containers =
45             new WeakIdentityTable<Class JavaDoc, ConstantContainer>();
46
47     private static class ConstantContainer {
48
49         private Enum_[] constants;
50
51         public synchronized Enum_[] getConstants() {
52             return constants;
53         }
54
55         public synchronized void setConstants(Enum_[] constants) {
56             this.constants = constants;
57         }
58
59     }
60
61     private final String JavaDoc name;
62
63     private final int ordinal;
64
65     protected Enum_(String JavaDoc name, int ordinal) {
66         this.name = name;
67         this.ordinal = ordinal;
68     }
69
70     public final String JavaDoc name() {
71         return name;
72     }
73
74     public final int ordinal() {
75         return ordinal;
76     }
77
78     public String JavaDoc toString() {
79         return name;
80     }
81
82     public final boolean equals(Object JavaDoc other) {
83         return this == other;
84     }
85
86     public final int hashCode() {
87         return super.hashCode();
88     }
89
90     protected final Object JavaDoc clone() throws CloneNotSupportedException JavaDoc {
91         throw new CloneNotSupportedException JavaDoc();
92     }
93
94     public final int compareTo(E other) {
95         if (this.getClass() != other.getClass() && this.getDeclaringClass() != other.getDeclaringClass()) {
96             throw new ClassCastException JavaDoc();
97         }
98         return this.ordinal - other.ordinal;
99     }
100
101     public final Class JavaDoc<E> getDeclaringClass() {
102         Class JavaDoc clazz = getClass();
103         Class JavaDoc zuper = clazz.getSuperclass();
104         return (zuper == Enum_.class) ? clazz : zuper;
105     }
106
107     public static <T extends Enum_<T>> T valueOf(Class JavaDoc<T> enumType, String JavaDoc name) {
108         if (name == null) throw new NullPointerException JavaDoc("Name is null");
109         T[] enums = (T[]) getEnumConstants(enumType);
110         if (enums == null) throw new IllegalArgumentException JavaDoc(enumType.getName() + " is not an enum type");
111         for (T currentEnum : enums) {
112             if (currentEnum.name.equals(name)) return currentEnum;
113         }
114         throw new IllegalArgumentException JavaDoc("No enum const " + enumType + "." + name);
115     }
116
117     protected Object JavaDoc readResolve() throws InvalidObjectException {
118         try {
119             return valueOf(getDeclaringClass(), name);
120         } catch (IllegalArgumentException JavaDoc e) {
121             InvalidObjectException exception = new InvalidObjectException(e.getMessage());
122             exception.initCause(e);
123             throw exception;
124         }
125     }
126
127     protected static Enum_[] getEnumConstants(Class JavaDoc aClass) {
128         ConstantContainer container = containers.lookup(aClass);
129         if (container != null) {
130             return container.getConstants();
131         }
132         if (aClass.getSuperclass() != Enum_.class) return null;
133         initialize(aClass);
134         container = containers.lookup(aClass);
135         return container == null ? null : container.getConstants();
136     }
137
138     protected static void setEnumConstants(Class JavaDoc aClass, Enum_[] enumConstants) {
139         ConstantContainer container = new ConstantContainer();
140         container.setConstants(enumConstants);
141         containers.putIfAbsent(aClass, container);
142     }
143
144     private static void initialize(final Class JavaDoc aClass) {
145         AccessController.doPrivileged(new PrivilegedAction<Object JavaDoc>() {
146             public Object JavaDoc run() {
147                 try {
148                     Class.forName(aClass.getName(), true, aClass.getClassLoader());
149                     if (containers.lookup(aClass) == null) {
150                         Method JavaDoc method = aClass.getMethod("values");
151                         method.setAccessible(true);
152                         method.invoke(null);
153                     }
154                 } catch (Exception JavaDoc e) {
155                     //ignore
156
}
157                 return null;
158             }
159         });
160     }
161
162 }
163
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