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19 package org.netbeans.mdr.persistence.btreeimpl.btreeindex;
20
21 import org.netbeans.mdr.persistence.*;
22 import org.netbeans.mdr.util.MapEntryImpl;
23 import java.lang.ref.WeakReference  ;
24 import java.util.*;
25 import java.text.*;
26
27
33 public class MultivaluedBtree extends Btree implements MultivaluedIndex {
34
35 private WeakHashMap listsByKey_cache = new WeakHashMap ();
37
38 public MultivaluedBtree(String name, Storage.EntryType keyType,
39 Storage.EntryType dataType,
40 boolean uniqueValues,
41 BtreePageSource pageSource)
42 throws StorageException {
43 super(name, keyType, dataType, pageSource);
44 this.uniqueValues = uniqueValues;
45 }
46
47 protected void init() throws StorageException {
48 uniqueKeys = false;
49 super.init();
50 }
51
52
56 public MultivaluedBtree() {
57 }
58
59
66 public Collection getItems(Object key) throws StorageException {
67 WeakReference ref = (WeakReference ) listsByKey_cache.get (new BtreeListByKey.Key (key));
68 BtreeListByKey list = null;
69 if (ref != null)
70 list = (BtreeListByKey) ref.get();
71 if (list == null) {
72 list = new BtreeListByKey(this, key);
73 listsByKey_cache.put (list, new WeakReference (list));
74 }
75 return list;
76 }
77
78
85 public Collection getObjects(Object key, SinglevaluedIndex repos) throws StorageException {
86 WeakReference ref = (WeakReference ) listsByKey_cache.get (new BtreeListByKey.Key (key));
87 BtreeListByKey list = null;
88 if (ref != null)
89 list = (BtreeListByKey) ref.get();
90 if (list == null) {
91 list = new BtreeListByKey(this, key);
92 listsByKey_cache.put (list, new WeakReference (list));
93 }
94 return new BtreeListByKeyRepos(list, repos);
95 }
96
97
102 public boolean isUnique() {
103 return uniqueValues;
104 }
105
106
113 public boolean remove(Object key, Object value) throws StorageException {
114 beginWrite();
115 try {
116 byte[] keyBuffer, dataBuffer;
117 boolean result;
118
119 if ((keyBuffer = keyInfo.toBuffer(key)) == null) {
120 throw new StorageBadRequestException(
121 MessageFormat.format(
122 "Invalid key type for this index: {0} received, {1} expected",
123 new Object [] {
124 key.getClass().getName(),
125 keyInfo.typeName()} ));
126 }
127
128 if ((dataBuffer = dataInfo.toBuffer(value)) == null) {
129 throw new StorageBadRequestException(
130 MessageFormat.format(
131 "Invalid data type for this index: {0} received, {1} expected",
132 new Object [] {
133 value.getClass().getName(),
134 dataInfo.typeName()} ));
135 }
136
137 BtreePage root = pageSource.getPage(rootPageId, this);
138 result = root.remove(keyBuffer, dataBuffer);
139 if (result)
140 updateKeyModCount (key);
141 pageSource.unpinPage(root);
142 return result;
143 } finally {
144 endWrite();
145 }
146 }
147
148 public void add(Object key, Object data) throws StorageException {
149 super.add (key, data);
150 updateKeyModCount (key);
151 }
152
153 public boolean remove(Object key) throws StorageException {
154 boolean result = super.remove (key);
155 if (result)
156 updateKeyModCount (key);
157 return result;
158 }
159
160
164 public synchronized Collection queryByKeyPrefix (Object prefix, SinglevaluedIndex primaryIndex) throws StorageException {
165 if (keyType != Storage.EntryType.STRING) {
166 throw new UnsupportedOperationException ("Key type must be EntryType.STRING");
167 }
168
169 List result = new LinkedList ();
170 byte [] prefixBytes = keyInfo.toBuffer (prefix);
171 SearchResult location = getLocation (prefixBytes);
172 if (location.entryNum == location.page.numEntries())
173 BtreePage.getNext (null, location);
174
175 while ((location.entryNum < location.page.numEntries()) &&
176 SinglevaluedBtree.isPrefix (prefixBytes, location.page.getKey (location.entryNum))) {
177 byte [] key = location.page.getKey (location.entryNum);
178 Object keyObject = keyInfo.objectFromBuffer (key, primaryIndex);
179 Collection data = getObjects (keyObject, primaryIndex);
180 Object entry = new MapEntryImpl (keyObject, data);
181 result.add (entry);
182 int size = data.size ();
183 location.page.findNth (location, key, size, false);
184 } return result;
186 }
187
188 private static boolean isPrefix (byte [] prefix, byte [] key) {
189 if (prefix.length > key.length)
190 return false;
191 for (int x = 0; x < prefix.length; x++) {
192 if (prefix [x] != key [x])
193 return false;
194 }
195 return true;
196 }
197
198
202 protected void updateKeyModCount (Object key) {
203 WeakReference ref = (WeakReference ) listsByKey_cache.get (new BtreeListByKey.Key (key));
204 if (ref == null)
205 return;
206 BtreeListByKey list = null;
207 list = (BtreeListByKey) ref.get ();
208 if (list != null)
209 list.increaseModCount ();
210 }
211
212 }
213 |
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