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1 package com.jofti.store;
2
3 import java.io.IOException  ;
4 import java.io.ObjectInputStream ;
5 import java.io.ObjectOutputStream ;
6 import java.nio.ByteBuffer ;
7 import java.util.HashMap ;
8 import java.util.Iterator ;
9 import java.util.Map ;
10
11 import org.apache.commons.logging.Log;
12 import org.apache.commons.logging.LogFactory;
13
14 import com.jofti.btree.IPage;
15 import com.jofti.btree.KeyValueObject;
16 import com.jofti.btree.LeafNodeEntry;
17 import com.jofti.btree.MaxLeafNodeEntry;
18 import com.jofti.btree.ValueObject;
19 import com.jofti.core.IStoreManager;
20 import com.jofti.exception.JoftiException;
21 import com.jofti.util.ByteBufferArrayInputStream;
22 import com.jofti.util.FastByteArrayOutputStream;
23
24
31 public class ExternalisableHelper {
32
33 private static final byte STRING = 0;
34
35 private static final byte LONG = 1;
36
37 private static final byte INTEGER = 2;
38
39 private static final byte BOOLEAN = 3;
40
41 private static final byte OTHER = 4;
42
43 private static final byte MAX_ENTRY = 0;
44
45 private static final byte LEAF_ENTRY = 1;
46
47 private static final byte NULL_ENTRY = 2;
48
49 private static final byte KEY_VALUE = 1;
50
51 private static final byte VALUE_OBJECT = 2;
52
53 private static Log log = LogFactory.getLog(ExternalisableHelper.class);
54
55 FastByteArrayOutputStream nodeFbos = null;
56
57 ByteBufferArrayInputStream bybuf = null;
58
59 ObjectOutputStream nodeOut = null;
60
61 AbstractStoreManager manager = null;
62
63 int nodeSize = 0;
64
65 public void init(int nodeSize, int blockSize, IStoreManager manager)
66 throws JoftiException
67 {
68 bybuf = new ByteBufferArrayInputStream(null);
69 nodeFbos = new FastByteArrayOutputStream(blockSize);
70 try {
71 nodeOut = new ObjectOutputStream (nodeFbos);
72
73 nodeOut.useProtocolVersion(1);
74 } catch (Exception e) {
75 throw new JoftiException(e);
76 }
77 this.nodeSize = nodeSize;
78 this.manager = (AbstractStoreManager) manager;
79 }
80
81
82 public LeafNodeEntry convertFromStore(ByteBuffer buf)
83 throws JoftiException
84 {
85
86 ObjectInputStream in = null;
87 LeafNodeEntry entry = null;
88
89 try {
90
91 bybuf.resetData(buf);
92 in = new ObjectInputStream (bybuf);
94
95 byte type = in.readByte();
97
98 if (type == NULL_ENTRY) {
99 return null;
101 } else if (type == MAX_ENTRY) {
102
103 entry = new MaxLeafNodeEntry();
104 } else {
105 if (entry == null) {
106 entry = new LeafNodeEntry();
107 }
108 }
109
110 Object obj = readValue(in);
112
113 type = in.readByte();
115
116 int dimension = in.readInt();
118
119 if (type == KEY_VALUE) {
120
121 byte j = in.readByte();
125
126 Map map = new HashMap (j);
127 for (int k = 0; k < j; k++) {
128 map.put(readValue(in), readValue(in));
129 }
130 entry.value = new KeyValueObject(dimension, (Comparable ) obj,
131 map);
132
133 } else {
134
135 entry.value = new ValueObject(dimension, (Comparable ) obj);
136
137 }
138 int l = in.readInt();
140
141 for (int k = 0; k < l; k++) {
142 entry.addUniqueId(readValue(in));
143 }
144
145 } catch (Exception e) {
146 throw new JoftiException("Unable to read entry " + buf, e);
147 } finally {
148 if (in != null) {
150 try {
151 in.close();
152 } catch (Exception e) {
153 }
155 in = null;
156 }
157 }
158
159 return entry;
160
161 }
162
163 public byte[] convertForStore(LeafNodeEntry entry) throws JoftiException
164 {
165 byte[] res =null;
166 try {
167 if (entry instanceof MaxLeafNodeEntry) {
168 nodeOut.writeByte(MAX_ENTRY);
170
171 } else {
172 nodeOut.writeByte(LEAF_ENTRY);
174 }
175
177 ValueObject valObj = (ValueObject) entry.value;
178
179 writeValue(nodeOut, valObj.getRealValue());
180
181 if (entry.value instanceof KeyValueObject) {
183 nodeOut.writeByte(KEY_VALUE);
185
186 nodeOut.writeInt(((ValueObject) entry.value).getDimension());
188
189 Map map = ((KeyValueObject) valObj).getAttributes();
191
192 nodeOut.writeByte((byte) map.size());
194 Iterator it = map.entrySet().iterator();
195 for (int i = 0; i < map.size(); i++) {
196 Map.Entry mapEntry = (Map.Entry ) it.next();
197 writeValue(nodeOut, mapEntry.getKey());
198 writeValue(nodeOut, mapEntry.getValue());
199
200 }
201
202 } else {
203 nodeOut.writeByte(VALUE_OBJECT);
205
206 nodeOut.writeInt(((ValueObject) entry.value).getDimension());
208 }
209
210 int size = entry.getUniqueIdSize();
211
212 nodeOut.writeInt(size);
213 if (size > 0) {
214 Iterator it = entry.uniqueIdSet.iterator();
215 for (int i = 0; i < size; i++) {
216 writeValue(nodeOut, it.next());
217 }
218 }
219
220 nodeOut.flush();
221 size = nodeFbos.getSize();
222 byte[] tempData = nodeFbos.getByteArray();
223 res = new byte[size];
224
225 System.arraycopy(tempData, 0, res, 0, size);
226
227 nodeOut.reset();
228 nodeFbos.reset();
229
230 } catch (Throwable t){
231 throw new JoftiException("Unable to serialize entry "+ entry,t);
232 }
233 return res;
234
235 }
236
237
238 IPage readExternalBuffer(java.nio.ByteBuffer buffer, int numberEntries)
239 throws JoftiException
240 {
241
242 IPage page = manager.doGetNewPage(buffer.limit());
243
244 ByteBuffer pBuf = page.getBuffer();
245
246 int[] pointers = page.getPointers();
247
248 try {
249 pBuf.clear();
250 pBuf.put(buffer);
251 pBuf.flip();
252 pBuf.mark();
253
254 for (int i = 0; i < numberEntries; i++) {
256
257 pointers[i] = pBuf.position();
259 int size = pBuf.getInt();
260 pBuf.position(pBuf.position() + size);
262
263 }
264 pBuf.reset();
265
266 } catch (Throwable e) {
267 log.fatal("expected to read " + numberEntries + " pos at "
268 + buffer);
269 throw new JoftiException("unable to read block ", e);
270 }
271 return page;
272
273 }
274
275
276 private void writeValue(ObjectOutputStream out, Object obj)
277 throws IOException {
278 Class clazz = obj.getClass();
279 if (clazz == String .class) {
280 out.writeByte(STRING);
281
282 out.writeUTF((String ) obj);
283
284 } else if (clazz == Integer .class) {
285 out.writeByte(INTEGER);
286 out.writeInt(((Integer ) obj).intValue());
287
288 } else if (clazz == Long .class) {
289 out.writeByte(LONG);
290 out.writeLong(((Long ) obj).longValue());
291 } else {
292 out.writeByte(OTHER);
293 out.writeObject(obj);
294 }
295 }
296
297 private Object readValue(ObjectInputStream in) throws IOException ,
298 ClassNotFoundException {
299 int valType = in.readByte();
300 switch (valType) {
301 case STRING:
302 return in.readUTF();
303 case INTEGER:
304 return new Integer (in.readInt());
305
306 case LONG:
307 return new Long (in.readLong());
308 default:
309 return in.readObject();
310 }
311
312 }
313 } |
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