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1 package org.myoodb.core.storage;
25
26 import java.io.*;
27
28 import org.myoodb.util.*;
29 import org.myoodb.core.*;
30
31 public final class Cluster implements Externalizable, AbstractCluster
32 {
33 private static final org.apache.log4j.Logger LOGGER = org.apache.log4j.Logger.getLogger(Cluster.class);
34
35 private AbstractLock m_lock;
36 private AbstractObjectContainer m_container;
37
38 public static File getMostCurrentCluster(String  basename, Identifier objectId)
39 {
40 File current = new File(basename + ClusterStore.SUFFIX_CLUSTER);
41
42 final String strId = objectId.toString();
43 final String strIdWithSuffix = strId + ClusterStore.SUFFIX_SEPARATOR;
44 final String strIdClusterPath = ClusterStore.getDirectoryName(strId, objectId.isRoot());
45
46 FilenameFilter clusterFilter = new FilenameFilter()
47 {
48 public boolean accept(File dir, String name)
49 {
50 return (name.startsWith(strIdWithSuffix) == true) && (name.endsWith(ClusterStore.SUFFIX_TEMP) == false);
51 }
52 };
53
54 long lastTX = -1;
55 File file = new File(strIdClusterPath);
56 String [] fileList = file.list(clusterFilter);
57 for (int i = 0; i < fileList.length; i++)
58 {
59 String [] tokens = fileList[i].split("\\.");
60
61 if (tokens.length == 3)
62 {
63 long tmpTX = Long.parseLong(tokens[1]);
64
65 if (tmpTX > lastTX)
66 {
67 current = new File(strIdClusterPath + File.separator + fileList[i]);
68 lastTX = tmpTX;
69 }
70 }
71 }
72
73 return current;
74 }
75
76 public static void delete(Identifier id) throws IOException
77 {
78 File file = new File(ClusterStore.getBasename(id) + ClusterStore.SUFFIX_CLUSTER);
79
80 if (file.exists() == true)
81 {
82 org.myoodb.core.FileHelper.delete(file);
83 }
84
85 File dfile = new File(ClusterStore.getDirectoryName(id.toString(), id.isRoot()));
87 String [] files = dfile.list();
88
89 if ((files != null) && (files.length == 0))
90 {
91 org.myoodb.core.FileHelper.delete(dfile);
92 }
93 }
94
95 public Cluster()
96 {
97 }
98
99 public Cluster(AbstractObjectContainer container, AbstractLock lock)
100 {
101 m_lock = lock;
102 setContainer(container);
103 }
104
105 protected void writeChild(AbstractTransaction tx) throws IOException
106 {
107 String basename = ClusterStore.getBasename(getObjectId());
108
109 File child = new File(basename +
110 ClusterStore.SUFFIX_SEPARATOR +
111 tx.getTransactionIdentifier() +
112 ClusterStore.SUFFIX_CHILD);
113
114 File parent = getMostCurrentCluster(basename, getObjectId());
115
116 InputStream in = null;
117 OutputStream out = null;
118 try
119 {
120 in = new FileInputStream(parent);
121 out = new FileOutputStream(child);
122
123 int offset = 0;
124 int size = in.available();
125 byte[] buffer = new byte[in.available()];
126
127 while (offset < size)
128 {
129 int bytesRead = in.read(buffer, offset, (size - offset));
130 if (bytesRead == -1)
131 {
132 break;
133 }
134
135 out.write(buffer, offset, (size - offset));
136 offset += bytesRead;
137 }
138 }
139 finally
140 {
141 if (in != null)
142 {
143 in.close();
144 }
145 if (out != null)
146 {
147 out.close();
148 }
149 }
150 }
151
152 protected void commitChild(AbstractTransaction tx) throws IOException
153 {
154 String basename = ClusterStore.getBasename(getObjectId());
155
156 File temp = new File(basename +
157 ClusterStore.SUFFIX_SEPARATOR +
158 tx.getTransactionIdentifier() +
159 ClusterStore.SUFFIX_TEMP);
160
161 File child = new File(basename +
162 ClusterStore.SUFFIX_SEPARATOR +
163 tx.getTransactionIdentifier() +
164 ClusterStore.SUFFIX_CHILD);
165
166 if (temp.exists() == true)
167 {
168 org.myoodb.core.FileHelper.delete(temp);
169 }
170
171 if (child.renameTo(temp) == false)
172 {
173 throw new IOException("Unable to rename \"child\" file to \"temp\":" + child + " " + temp + " " + tx);
174 }
175
176 File parent = getMostCurrentCluster(basename, getObjectId());
177
178 if (parent.exists() == true)
179 {
180 org.myoodb.core.FileHelper.delete(parent);
181 }
182
183 if (temp.renameTo(parent) == false)
184 {
185 throw new IOException("Unable to rename \"temp\" file to \"parent\":" + temp + " " + parent + " " + tx);
186 }
187 }
188
189 protected void deleteChild(AbstractTransaction tx) throws IOException
190 {
191 String basename = ClusterStore.getBasename(getObjectId());
192
193 File child = new File(basename +
194 ClusterStore.SUFFIX_SEPARATOR +
195 tx.getTransactionIdentifier() +
196 ClusterStore.SUFFIX_CHILD);
197
198 if (child.exists() == true)
199 {
200 org.myoodb.core.FileHelper.delete(child);
201 }
202 }
203
204 protected Identifier getObjectId()
205 {
206 return m_container.getObjectId();
207 }
208
209 public AbstractLock getLock()
210 {
211 return m_lock;
212 }
213
214 public void setLock(AbstractLock lock)
215 {
216 m_lock = lock;
217 }
218
219 public void setContainer(AbstractObjectContainer container)
220 {
221 m_container = container;
222 m_container.setCluster(this);
223 }
224
225 public AbstractObjectContainer getContainer()
226 {
227 return m_container;
228 }
229
230 public void setAssociatedTransaction(AbstractTransaction tx) throws IOException
231 {
232 if (tx.getTransactionType() == AbstractTransaction.EXPLICIT_TRANSACTION)
233 {
234 writeChild(tx);
235 }
236 }
237
238 public void commit(AbstractTransaction tx) throws IOException
239 {
240 if (tx.getStagingTransactionFlag() == false)
241 {
242 if (tx.getTransactionType() == AbstractTransaction.EXPLICIT_TRANSACTION)
243 {
244 commitChild(tx);
245 }
246
247 if (tx.isExplicitPiggyBack() == false)
248 {
249 m_lock.release(tx);
250 }
251 }
252 }
253
254 public void abort(AbstractTransaction tx) throws IOException
255 {
256 if (tx.getTransactionType() == AbstractTransaction.EXPLICIT_TRANSACTION)
257 {
258 deleteChild(tx);
259 }
260
261 m_lock.release(tx);
262 }
263
264 public boolean delete(AbstractTransaction tx) throws IOException
265 {
266 boolean isBase = false;
267
268 if (tx.getStagingTransactionFlag() == false)
269 {
270 String basename = ClusterStore.getBasename(getObjectId());
271
272 File child = new File(basename +
273 ClusterStore.SUFFIX_SEPARATOR +
274 tx.getTransactionIdentifier() +
275 ClusterStore.SUFFIX_CHILD);
276
277 File base = new File(basename + ClusterStore.SUFFIX_CLUSTER);
278
279 if (child.equals(base) == true)
280 {
281 isBase = true;
282 }
283
284 if (child.exists() == true)
285 {
286 org.myoodb.core.FileHelper.delete(child);
287 }
288
289 File dfile = new File(ClusterStore.getDirectoryName(getObjectId().toString(), getObjectId().isRoot()));
291 String [] files = dfile.list();
292
293 if ((files != null) && (files.length == 0))
294 {
295 org.myoodb.core.FileHelper.delete(dfile);
296 }
297 }
298
299 return isBase;
300 }
301
302 public void read(String file) throws IOException, ClassNotFoundException
303 {
304 ObjectInputStream in = new FastObjectInputStream(new BufferedInputStream(new FileInputStream(file)));
305
306 try
307 {
308 readExternal(in);
309 }
310 finally
311 {
312 in.close();
313 }
314 }
315
316 public void write(String filename) throws IOException
317 {
318 java.util.ConcurrentModificationException globalError = null;
319
320 for (int i = 0; i < ClusterStore.CONCURRENCY_RETRY; i++)
321 {
322 try
323 {
324 ObjectOutputStream out = new FastObjectOutputStream(new BufferedOutputStream(new FileOutputStream(filename)));
325
326 try
327 {
328 writeExternal(out);
329 globalError = null;
330 break;
331 }
332 finally
333 {
334 out.close();
335 }
336 }
337 catch (java.util.ConcurrentModificationException e)
338 {
339 LOGGER.warn(null, e);
340
341 try
342 {
343 Thread.sleep(100);
344 }
345 catch (java.lang.InterruptedException ee)
346 {
347 }
349
350 globalError = e;
351 }
352 }
353
354 if (globalError != null)
355 {
356 throw globalError;
357 }
358 }
359
360 public void write() throws IOException
361 {
362 write(ClusterStore.getBasename(getObjectId()) + ClusterStore.SUFFIX_CLUSTER);
363 }
364
365 public void writeExternal(ObjectOutput out) throws IOException
366 {
367 out.writeObject(m_lock);
368 out.writeObject(m_container);
369 }
370
371 public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
372 {
373 m_lock = (AbstractLock) in.readObject();
374 setContainer((AbstractObjectContainer) in.readObject());
375 }
376 }
377 |
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