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1 /* Copyright 2004 The Apache Software Foundation
2 *
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 package org.apache.xmlbeans;
17
18 import java.util.HashMap;
19 import java.util.Map;
20 import java.util.List;
21 import java.util.ArrayList;
22
23 /**
24 * The base class for code-generated string enumeration value classes.
25 * <p>
26 * Subclasses are intended to be final types with a finite set of
27 * singleton instances. Each instance has a string value, which
28 * it returns via {@link #toString}, and an int value for the purpose
29 * of switching in case statements, returned via {@link #intValue}.
30 * <p>
31 * Each subclass manages an instance of {@link StringEnumAbstractBase.Table},
32 * which holds all the singleton instances for the subclass. A Table
33 * can return a singleton instance given a String or an integer code.
34 */
35 public class StringEnumAbstractBase implements java.io.Serializable
36 {
37 private static final long serialVersionUID = 1L;
38
39 private String _string;
40 private int _int;
41
42 /**
43 * Singleton instances should only be created by subclasses.
44 */
45 protected StringEnumAbstractBase(String s, int i)
46 { _string = s; _int = i; }
47
48 /** Returns the underlying string value */
49 public final String toString()
50 { return _string; }
51 /** Returns an int code that can be used for switch statements */
52 public final int intValue()
53 { return _int; }
54 /** Returns the hash code of the underlying string */
55 public final int hashCode()
56 { return _string.hashCode(); }
57
58 /**
59 * Used to manage singleton instances of enumerations.
60 * Each subclass of StringEnumAbstractBase has an instance
61 * of a table to hold the singleton instances.
62 */
63 public static final class Table
64 {
65 private Map _map;
66 private List _list;
67 public Table(StringEnumAbstractBase[] array)
68 {
69 _map = new HashMap(array.length);
70 _list = new ArrayList(array.length + 1);
71 for (int i = 0; i < array.length; i++)
72 {
73 _map.put(array[i].toString(), array[i]);
74 int j = array[i].intValue();
75 while (_list.size() <= j)
76 _list.add(null);
77 _list.set(j, array[i]);
78 }
79 }
80
81 /** Returns the singleton for a {@link String}, or null if none. */
82 public StringEnumAbstractBase forString(String s)
83 {
84 return (StringEnumAbstractBase)_map.get(s);
85 }
86 /** Returns the singleton for an int code, or null if none. */
87 public StringEnumAbstractBase forInt(int i)
88 {
89 if (i < 0 || i > _list.size())
90 return null;
91 return (StringEnumAbstractBase)_list.get(i);
92 }
93 /** Returns the last valid int code (the first is 1; zero is not used). */
94 public int lastInt()
95 {
96 return _list.size() - 1;
97 }
98 }
99 }