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1
21 package com.db4o;
22
23 import com.db4o.ext.*;
24 import com.db4o.foundation.*;
25 import com.db4o.inside.*;
26 import com.db4o.inside.btree.*;
27 import com.db4o.inside.marshall.*;
28 import com.db4o.inside.slots.*;
29
30
33 public class YapFieldUUID extends YapFieldVirtual {
34
35 private static final int LINK_LENGTH = YapConst.LONG_LENGTH + YapConst.ID_LENGTH;
36
37 YapFieldUUID(YapStream stream) {
38 super();
39 i_name = YapConst.VIRTUAL_FIELD_PREFIX + "uuid";
40 i_handler = new YLong(stream);
41 }
42
43 public void addFieldIndex(MarshallerFamily mf, YapClass yapClass, YapWriter writer, Slot oldSlot) {
44
45 boolean isnew = (oldSlot == null);
46
47 int offset = writer._offset;
48 int db4oDatabaseIdentityID = writer.readInt();
49 long uuid = writer.readLong();
50 writer._offset = offset;
51
52 YapFile yf = (YapFile)writer.getStream();
53
54 if( (uuid == 0 || db4oDatabaseIdentityID == 0) && writer.getID() > 0 && ! isnew){
55 DatabaseIdentityIDAndUUID identityAndUUID = readDatabaseIdentityIDAndUUID(yf, yapClass, oldSlot, false);
56 db4oDatabaseIdentityID = identityAndUUID.databaseIdentityID;
57 uuid = identityAndUUID.uuid;
58 }
59
60 if(db4oDatabaseIdentityID == 0){
61 db4oDatabaseIdentityID = yf.identity().getID(writer.getTransaction());
62 }
63
64 if(uuid == 0){
65 uuid = yf.generateTimeStampId();
66 }
67
68 writer.writeInt(db4oDatabaseIdentityID);
69 writer.writeLong(uuid);
70
71 if(isnew){
72 addIndexEntry(writer, new Long  (uuid));
73 }
74 }
75
76 static class DatabaseIdentityIDAndUUID {
77 public int databaseIdentityID;
78 public long uuid;
79 public DatabaseIdentityIDAndUUID(int databaseIdentityID_, long uuid_) {
80 databaseIdentityID = databaseIdentityID_;
81 uuid = uuid_;
82 }
83 }
84
85 private DatabaseIdentityIDAndUUID readDatabaseIdentityIDAndUUID(YapStream stream, YapClass yapClass, Slot oldSlot, boolean checkClass) {
86 if(DTrace.enabled){
87 DTrace.REREAD_OLD_UUID.logLength(oldSlot.getAddress(), oldSlot.getLength());
88 }
89 YapReader reader = stream.readReaderByAddress(oldSlot.getAddress(), oldSlot.getLength());
90 if(checkClass){
91 YapClass realClass = YapClass.readClass(stream,reader);
92 if(realClass != yapClass){
93 return null;
94 }
95 }
96 if (null == yapClass.findOffset(reader, this)) {
97 return null;
98 }
99 return new DatabaseIdentityIDAndUUID(reader.readInt(), reader.readLong());
100 }
101
102 public void delete(MarshallerFamily mf, YapWriter a_bytes, boolean isUpdate) {
103 if(isUpdate){
104 a_bytes.incrementOffset(linkLength());
105 return;
106 }
107 a_bytes.incrementOffset(YapConst.INT_LENGTH);
108 long longPart = a_bytes.readLong();
109 if(longPart > 0){
110 YapStream stream = a_bytes.getStream();
111 if (stream.maintainsIndices()){
112 removeIndexEntry(a_bytes.getTransaction(), a_bytes.getID(), new Long (longPart));
113 }
114 }
115 }
116
117 public boolean hasIndex() {
118 return true;
119 }
120
121 public BTree getIndex(Transaction transaction) {
122 ensureIndex(transaction);
123 return super.getIndex(transaction);
124 }
125
126 protected void rebuildIndexForObject(YapFile stream, YapClass yapClass, int objectId) {
127 DatabaseIdentityIDAndUUID data = readDatabaseIdentityIDAndUUID(stream, yapClass, ((YapFileTransaction)stream.getSystemTransaction()).getCurrentSlotOfID(objectId), true);
128 if (null == data) {
129 return;
130 }
131 addIndexEntry(stream.getSystemTransaction(), objectId, new Long (data.uuid));
132 }
133
134 private void ensureIndex(Transaction transaction) {
135 if (null == transaction) {
136 throw new ArgumentNullException();
137 }
138 if (null != super.getIndex(transaction)) {
139 return;
140 }
141 YapFile file = ((YapFile)transaction.stream());
142 SystemData sd = file.systemData();
143 if(sd == null){
144 return;
146 }
147 initIndex(transaction, sd.uuidIndexId());
148 if (sd.uuidIndexId() == 0) {
149 sd.uuidIndexId(super.getIndex(transaction).getID());
150 file.getFileHeader().writeVariablePart(file, 1);
151 }
152 }
153
154 void instantiate1(Transaction a_trans, YapObject a_yapObject, YapReader a_bytes) {
155 int dbID = a_bytes.readInt();
156 YapStream stream = a_trans.stream();
157 stream.showInternalClasses(true);
158 Db4oDatabase db = (Db4oDatabase)stream.getByID2(a_trans, dbID);
159 if(db != null && db.i_signature == null){
160 stream.activate2(a_trans, db, 2);
161 }
162 VirtualAttributes va = a_yapObject.virtualAttributes();
163 va.i_database = db;
164 va.i_uuid = a_bytes.readLong();
165 stream.showInternalClasses(false);
166 }
167
168 public int linkLength() {
169 return LINK_LENGTH;
170 }
171
172 void marshall1(YapObject a_yapObject, YapWriter a_bytes, boolean a_migrating, boolean a_new) {
173 YapStream stream = a_bytes.getStream();
174 Transaction trans = a_bytes.getTransaction();
175 boolean indexEntry = a_new && stream.maintainsIndices();
176 int dbID = 0;
177 VirtualAttributes attr = a_yapObject.virtualAttributes();
178
179 boolean linkToDatabase = ! a_migrating;
180 if(attr != null && attr.i_database == null) {
181 linkToDatabase = true;
182 }
183 if(linkToDatabase){
184 Db4oDatabase db = stream.identity();
185 if(db == null){
186 attr = null;
188 }else{
189 if (attr.i_database == null) {
190 attr.i_database = db;
191
192 if (stream instanceof YapFile){
194 attr.i_uuid = stream.generateTimeStampId();
195 indexEntry = true;
196 }
197 }
198 db = attr.i_database;
199 if(db != null) {
200 dbID = db.getID(trans);
201 }
202 }
203 }else{
204 if(attr != null){
205 dbID = attr.i_database.getID(trans);
206 }
207 }
208 a_bytes.writeInt(dbID);
209 if(attr != null){
210 a_bytes.writeLong(attr.i_uuid);
211 if(indexEntry){
212 addIndexEntry(a_bytes, new Long (attr.i_uuid));
213 }
214 }else{
215 a_bytes.writeLong(0);
216 }
217 }
218
219 void marshallIgnore(YapReader writer) {
220 writer.writeInt(0);
221 writer.writeLong(0);
222 }
223
224 public Object [] objectAndYapObjectBySignature(final Transaction transaction, final long longPart, final byte[] signature) {
225 final BTreeRange range = search(transaction, new Long (longPart));
226 final Iterator4 keys = range.keys();
227 while (keys.moveNext()) {
228 final FieldIndexKey current = (FieldIndexKey) keys.current();
229 final Object [] objectAndYapObject = getObjectAndYapObjectByID(transaction, current.parentID(), signature);
230 if (null != objectAndYapObject) {
231 return objectAndYapObject;
232 }
233 }
234 return new Object [2];
235 }
236
237 protected Object [] getObjectAndYapObjectByID(Transaction transaction, int parentId, byte[] signature) {
238 Object [] arr = transaction.stream().getObjectAndYapObjectByID(
239 transaction, parentId);
240 if (arr[1] == null) {
241 return null;
242 }
243 YapObject yod = (YapObject) arr[1];
244 VirtualAttributes vad = yod.virtualAttributes(transaction);
245 if (!Arrays4.areEqual(signature, vad.i_database.i_signature)) {
246 return null;
247 }
248 return arr;
249 }
250
251 public void defragField(MarshallerFamily mf, ReaderPair readers) {
252 readers.copyID();
254 readers.incrementOffset(YapConst.LONG_LENGTH);
256 }
257 } |
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