01: /*
02: * Licensed to the Apache Software Foundation (ASF) under one or more
03: * contributor license agreements. See the NOTICE file distributed with
04: * this work for additional information regarding copyright ownership.
05: * The ASF licenses this file to You under the Apache License, Version 2.0
06: * (the "License"); you may not use this file except in compliance with
07: * the License. You may obtain a copy of the License at
08: *
09: * http://www.apache.org/licenses/LICENSE-2.0
10: *
11: * Unless required by applicable law or agreed to in writing, software
12: * distributed under the License is distributed on an "AS IS" BASIS,
13: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14: * See the License for the specific language governing permissions and
15: * limitations under the License.
16: */
17: package org.apache.commons.lang.enums;
18:
19: import java.util.Iterator;
20: import java.util.List;
21: import java.util.Map;
22:
23: /**
24: * Color enumeration which demonstrates how to define the constants in a
25: * different class to the Enum. The extra <code>static{}</code> block is
26: * needed to ensure that the enum constants are created before the
27: * static methods on the ColorEnum are used.
28: * <p>
29: * The class loader sees the two classes here as independent - the enum
30: * class is nested, not an inner class. The static block thus forces the
31: * class load of the outer class, which is needed to initialise the enums.
32: *
33: * @author Stephen Colebourne
34: * @version $Id: NestLinked.java 437554 2006-08-28 06:21:41Z bayard $
35: */
36:
37: public final class NestLinked {
38:
39: public static final ColorEnum RED = new ColorEnum("Red");
40: public static final ColorEnum GREEN = new ColorEnum("Green");
41: public static final ColorEnum BLUE = new ColorEnum("Blue");
42:
43: public NestLinked() {
44: super ();
45: }
46:
47: public static final class ColorEnum extends Enum {
48:
49: static {
50: // Explicitly reference the class where the enums are defined
51: Object obj = NestLinked.RED;
52: }
53:
54: private ColorEnum(String color) {
55: super (color);
56: }
57:
58: public static ColorEnum getEnum(String color) {
59: return (ColorEnum) getEnum(ColorEnum.class, color);
60: }
61:
62: public static Map getEnumMap() {
63: return getEnumMap(ColorEnum.class);
64: }
65:
66: public static List getEnumList() {
67: return getEnumList(ColorEnum.class);
68: }
69:
70: public static Iterator iterator() {
71: return iterator(ColorEnum.class);
72: }
73: }
74: }
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