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1
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12 package com.versant.core.jdo.sco;
13
14 import java.beans.DefaultPersistenceDelegate  ;
15 import java.beans.Encoder ;
16 import java.beans.Expression ;
17 import java.beans.Statement ;
18 import java.util.*;
19
20
29 public class PersistenceDelegateManager {
30
31
34 public static void register(Encoder encoder) {
35 encoder.setPersistenceDelegate(com.versant.core.jdo.sco.Date.class,
36 new SCOPersistenceDelegate(java.util.Date .class));
37
38 encoder.setPersistenceDelegate(SCOList.class, new SCOListPD(ArrayList.class));
39 encoder.setPersistenceDelegate(SCOArrayList.class, new SCOListPD(ArrayList.class));
40 encoder.setPersistenceDelegate(SCOVector.class, new SCOListPD(Vector.class));
41
42 encoder.setPersistenceDelegate(SCOHashMap.class, new SCOMapPD(HashMap.class));
43 encoder.setPersistenceDelegate(SCOHashtable.class, new SCOMapPD(Hashtable.class));
44 encoder.setPersistenceDelegate(SCOTreeMap.class, new SCOMapPD(TreeMap.class));
45 encoder.setPersistenceDelegate(SCOTreeSet.class, new SCOMapPD(TreeSet.class));
46
47 encoder.setPersistenceDelegate(SCOHashSet.class, new SCOCollectionPD(HashSet.class));
48 encoder.setPersistenceDelegate(SCOLinkedList.class, new SCOCollectionPD(LinkedList.class));
49 }
50
51 private static void invokeStatement(Object instance, String methodName,
52 Object [] args, Encoder out) {
53 out.writeStatement(new Statement (instance, methodName, args));
54 }
55
56 private static boolean equals(Object o1, Object o2) {
57 return (o1 == null) ? (o2 == null) : o1.equals(o2);
58 }
59
60 public static class SCOPersistenceDelegate extends DefaultPersistenceDelegate {
61
62 Class javaType;
63
64 public SCOPersistenceDelegate(Class javaType) {
65 this.javaType = javaType;
66 }
67
68 protected Expression instantiate(Object oldInstance, Encoder out) {
69
70 return new Expression (oldInstance,
71 javaType,
72 "new",
73 new Object []{});
74 }
75
76 protected boolean mutatesTo(Object oldInstance, Object newInstance) {
77 if (oldInstance != null && newInstance != null) {
78 return true;
79 }
80 return super.mutatesTo(oldInstance, newInstance);
81 }
82 }
83
84 public static class SCOCollectionPD extends SCOPersistenceDelegate {
85
86 public SCOCollectionPD(Class javaType) {
87 super(javaType);
88 }
89
90 protected void initialize(Class type, Object oldInstance,
91 Object newInstance, Encoder out) {
92 java.util.Collection oldO = (java.util.Collection ) oldInstance;
93 java.util.Collection newO = (java.util.Collection ) newInstance;
94
95 if (newO.size() != 0) {
96 PersistenceDelegateManager.invokeStatement(oldInstance, "clear", new Object []{}, out);
97 }
98 for (Iterator i = oldO.iterator(); i.hasNext();) {
99 PersistenceDelegateManager.invokeStatement(oldInstance, "add", new Object []{
100 i.next()}, out);
101 }
102 }
103 }
104
105 public static class SCOListPD extends SCOPersistenceDelegate {
106
107 public SCOListPD(Class javaType) {
108 super(javaType);
109 }
110
111 protected void initialize(Class type, Object oldInstance,
112 Object newInstance, Encoder out) {
113
114 java.util.List oldO = (java.util.List ) oldInstance;
115 java.util.List newO = (java.util.List ) newInstance;
116 int oldSize = oldO.size();
117 int newSize = (newO == null) ? 0 : newO.size();
118 if (oldSize < newSize) {
119 PersistenceDelegateManager.invokeStatement(oldInstance, "clear", new Object []{}, out);
120 newSize = 0;
121 }
122 for (int i = 0; i < newSize; i++) {
123 Object index = new Integer (i);
124
125 Expression oldGetExp = new Expression (oldInstance, "get", new Object []{
126 index});
127 Expression newGetExp = new Expression (newInstance, "get", new Object []{
128 index});
129 try {
130 Object oldValue = oldGetExp.getValue();
131 Object newValue = newGetExp.getValue();
132 out.writeExpression(oldGetExp);
133 if (!PersistenceDelegateManager.equals(newValue, out.get(oldValue))) {
134 PersistenceDelegateManager.invokeStatement(oldInstance, "set", new Object []{
135 index, oldValue}, out);
136 }
137 } catch (Exception e) {
138 out.getExceptionListener().exceptionThrown(e);
139 }
140 }
141 for (int i = newSize; i < oldSize; i++) {
142 PersistenceDelegateManager.invokeStatement(oldInstance, "add", new Object []{
143 oldO.get(i)}, out);
144 }
145 }
146
147 }
148
149 public static class SCOMapPD extends SCOPersistenceDelegate {
150
151 public SCOMapPD(Class javaType) {
152 super(javaType);
153 }
154
155 protected void initialize(Class type, Object oldInstance,
156 Object newInstance, Encoder out) {
157 java.util.Map oldMap = (java.util.Map ) oldInstance;
158 java.util.Map newMap = (java.util.Map ) newInstance;
159 if (newMap != null) {
162 java.util.Iterator newKeys = newMap.keySet().iterator();
163 while (newKeys.hasNext()) {
164 Object newKey = newKeys.next();
165 if (!oldMap.containsKey(newKey)) {
167 PersistenceDelegateManager.invokeStatement(oldInstance, "remove", new Object []{
168 newKey}, out);
169 }
170 }
171 }
172 java.util.Iterator oldKeys = oldMap.keySet().iterator();
174 while (oldKeys.hasNext()) {
175 Object oldKey = oldKeys.next();
176
177 Expression oldGetExp = new Expression (oldInstance, "get", new Object []{
178 oldKey});
179 Expression newGetExp = new Expression (newInstance, "get", new Object []{
181 oldKey});
182 try {
183 Object oldValue = oldGetExp.getValue();
184 Object newValue = newGetExp.getValue();
185 out.writeExpression(oldGetExp);
186 if (!PersistenceDelegateManager.equals(newValue, out.get(oldValue))) {
187 PersistenceDelegateManager.invokeStatement(oldInstance, "put", new Object []{
188 oldKey, oldValue}, out);
189 }
190 } catch (Exception e) {
191 out.getExceptionListener().exceptionThrown(e);
192 }
193 }
194 }
195 }
196 }
197 |
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