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1
8
9 package com.sleepycat.persist.impl;
10
11 import java.util.ArrayList  ;
12 import java.util.Collection ;
13 import java.util.HashSet ;
14 import java.util.LinkedList ;
15 import java.util.Map ;
16 import java.util.Set ;
17 import java.util.TreeSet ;
18
19 import com.sleepycat.bind.tuple.TupleBase;
20 import com.sleepycat.je.DatabaseEntry;
21 import com.sleepycat.persist.model.Persistent;
22 import com.sleepycat.persist.model.PersistentProxy;
23 import com.sleepycat.persist.raw.RawObject;
24
25
30 @Persistent
31 abstract class CollectionProxy<E>
32 implements PersistentProxy<Collection <E>> {
33
34 private E[] elements;
35
36 protected CollectionProxy() {}
37
38 public final void initializeProxy(Collection <E> collection) {
39 elements = (E[]) new Object [collection.size()];
40 int i = 0;
41 for (E element : collection) {
42 elements[i] = element;
43 i += 1;
44 }
45 }
46
47 public final Collection <E> convertProxy() {
48 Collection <E> collection = newInstance(elements.length);
49 for (E element : elements) {
50 collection.add(element);
51 }
52 return collection;
53 }
54
55 protected abstract Collection <E> newInstance(int size);
56
57 @Persistent(proxyFor=ArrayList .class)
58 static class ArrayListProxy<E> extends CollectionProxy<E> {
59
60 protected ArrayListProxy() {}
61
62 protected Collection <E> newInstance(int size) {
63 return new ArrayList <E>(size);
64 }
65 }
66
67 @Persistent(proxyFor=LinkedList .class)
68 static class LinkedListProxy<E> extends CollectionProxy<E> {
69
70 protected LinkedListProxy() {}
71
72 protected Collection <E> newInstance(int size) {
73 return new LinkedList <E>();
74 }
75 }
76
77 @Persistent(proxyFor=HashSet .class)
78 static class HashSetProxy<E> extends CollectionProxy<E> {
79
80 protected HashSetProxy() {}
81
82 protected Collection <E> newInstance(int size) {
83 return new HashSet <E>(size);
84 }
85 }
86
87 @Persistent(proxyFor=TreeSet .class)
88 static class TreeSetProxy<E> extends CollectionProxy<E> {
89
90 protected TreeSetProxy() {}
91
92 protected Collection <E> newInstance(int size) {
93 return new TreeSet <E>();
94 }
95 }
96
97 static Object [] getElements(RawObject collection) {
98 Object value = null;
99 while (value == null && collection != null) {
100 Map <String ,Object > values = collection.getValues();
101 if (values != null) {
102 value = values.get("elements");
103 if (value == null) {
104 collection = collection.getSuper();
105 }
106 }
107 }
108 if (value == null || !(value instanceof RawObject)) {
109 throw new IllegalStateException
110 ("Collection proxy for a secondary key field must " +
111 "contain a field named 'elements'");
112 }
113 RawObject rawObj = (RawObject) value;
114 Format format = (Format) rawObj.getType();
115 if (!format.isArray() ||
116 format.getComponentType().getId() != Format.ID_OBJECT) {
117 throw new IllegalStateException
118 ("Collection proxy 'elements' field must by an Object array");
119 }
120 return rawObj.getElements();
121 }
122
123 static void setElements(RawObject collection, Object [] elements) {
124 RawObject value = null;
125 while (value == null && collection != null) {
126 Map <String ,Object > values = collection.getValues();
127 if (values != null) {
128 value = (RawObject) values.get("elements");
129 if (value != null) {
130 values.put("elements",
131 new RawObject(value.getType(), elements));
132 } else {
133 collection = collection.getSuper();
134 }
135 }
136 }
137 if (value == null) {
138 throw new IllegalStateException ();
139 }
140 }
141
142 static void copyElements(RecordInput input,
143 Format format,
144 Format keyFormat,
145 Set results) {
146
150 RawObject collection = (RawObject) format.newInstance(input, true);
151 collection = (RawObject) format.readObject(collection, input, true);
152 Object [] elements = getElements(collection);
153 if (elements != null) {
154 for (Object elem : elements) {
155 RecordOutput output =
156 new RecordOutput(input.getCatalog(), true);
157 output.writeKeyObject(elem, keyFormat);
158 DatabaseEntry entry = new DatabaseEntry();
159 TupleBase.outputToEntry(output, entry);
160 results.add(entry);
161 }
162 }
163 }
164 }
165 |
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