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1
8
9 package com.sleepycat.persist.impl;
10
11 import java.lang.reflect.Array  ;
12 import java.util.Arrays ;
13 import java.util.HashSet ;
14 import java.util.IdentityHashMap ;
15 import java.util.List ;
16 import java.util.Map ;
17 import java.util.Set ;
18
19 import com.sleepycat.persist.raw.RawObject;
20
21
30 public class EnumFormat extends Format {
31
32 private static final long serialVersionUID = 1069833955604373538L;
33
34 private String [] names;
35 private transient Object [] values;
36
37 EnumFormat(Class type) {
38 super(type);
39 values = type.getEnumConstants();
40 names = new String [values.length];
41 for (int i = 0; i < names.length; i += 1) {
42 names[i] = ((Enum ) values[i]).name();
43 }
44 }
45
46 @Override
47 public boolean isEnum() {
48 return true;
49 }
50
51 @Override
52 public List <String > getEnumConstants() {
53 return Arrays.asList(names);
54 }
55
56 @Override
57 void collectRelatedFormats(Catalog catalog,
58 Map <String ,Format> newFormats) {
59 }
60
61 @Override
62 void initialize(Catalog catalog) {
63 if (values == null) {
64 Class cls = getType();
65 if (cls != null) {
66 values = new Object [names.length];
67 for (int i = 0; i < names.length; i += 1) {
68 values[i] = Enum.valueOf(cls, names[i]);
69 }
70 }
71 }
72 }
73
74 @Override
75 Object newArray(int len) {
76 return Array.newInstance(getType(), len);
77 }
78
79 @Override
80 public Object newInstance(EntityInput input, boolean rawAccess) {
81 int index = input.readEnumConstant(names);
82 if (rawAccess) {
83 return new RawObject(this, names[index]);
84 } else {
85 return values[index];
86 }
87 }
88
89 @Override
90 public Object readObject(Object o, EntityInput input, boolean rawAccess) {
91
92 return o;
93 }
94
95 @Override
96 void writeObject(Object o, EntityOutput output, boolean rawAccess) {
97 if (rawAccess) {
98 String name = ((RawObject) o).getEnum();
99 for (int i = 0; i < names.length; i += 1) {
100 if (names[i].equals(name)) {
101 output.writeEnumConstant(names, i);
102 return;
103 }
104 }
105 } else {
106 for (int i = 0; i < values.length; i += 1) {
107 if (o == values[i]) {
108 output.writeEnumConstant(names, i);
109 return;
110 }
111 }
112 }
113 throw new IllegalStateException ("Bad enum: " + o);
114 }
115
116 @Override
117 Object convertRawObject(Catalog catalog,
118 boolean rawAccess,
119 RawObject rawObject,
120 IdentityHashMap converted) {
121 String name = rawObject.getEnum();
122 for (int i = 0; i < names.length; i += 1) {
123 if (names[i].equals(name)) {
124 Object o = values[i];
125 converted.put(rawObject, o);
126 return o;
127 }
128 }
129 throw new IllegalArgumentException
130 ("Enum constant is not defined: " + name);
131 }
132
133 @Override
134 void skipContents(RecordInput input) {
135 input.skipFast(input.getPackedIntByteLength());
136 }
137
138 @Override
139 boolean evolve(Format newFormatParam, Evolver evolver) {
140 if (!(newFormatParam instanceof EnumFormat)) {
141 evolver.addEvolveError
142 (this, newFormatParam,
143 "Incompatible enum type changed detected",
144 "An enum class may not be changed to a non-enum type");
145
151 return false;
152 }
153 EnumFormat newFormat = (EnumFormat) newFormatParam;
154 if (Arrays.equals(names, newFormat.names)) {
155 evolver.useOldFormat(this, newFormat);
156 return true;
157 } else {
158 Set <String > oldNames = new HashSet <String >(Arrays.asList(names));
159 List <String > newNames = Arrays.asList(newFormat.names);
160 if (newNames.containsAll(oldNames)) {
161 evolver.useEvolvedFormat(this, newFormat, newFormat);
162 return true;
163 } else {
164 oldNames.removeAll(newNames);
165 evolver.addEvolveError
166 (this, newFormat,
167 "Incompatible enum type changed detected",
168 "Enum values may not be removed: " + oldNames);
169
175 return false;
176 }
177 }
178 }
179 }
180 |
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