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1 package org.apache.ojb.odmg.locking;
2
3
17
18 import java.io.BufferedOutputStream  ;
19 import java.io.ByteArrayOutputStream ;
20 import java.io.IOException ;
21 import java.io.InputStream ;
22 import java.io.ObjectInputStream ;
23 import java.io.ObjectOutputStream ;
24 import java.net.HttpURLConnection ;
25 import java.net.MalformedURLException ;
26 import java.net.ProtocolException ;
27 import java.net.URL ;
28 import java.util.Collection ;
29
30 import org.apache.ojb.broker.Identity;
31 import org.apache.ojb.broker.PersistenceBroker;
32 import org.apache.ojb.broker.PersistenceBrokerException;
33 import org.apache.ojb.broker.util.configuration.Configurable;
34 import org.apache.ojb.broker.util.configuration.Configuration;
35 import org.apache.ojb.broker.util.configuration.ConfigurationException;
36 import org.apache.ojb.broker.util.logging.Logger;
37 import org.apache.ojb.broker.util.logging.LoggerFactory;
38 import org.apache.ojb.odmg.TransactionImpl;
39 import org.apache.ojb.odmg.TxManagerFactory;
40
41
46 public class RemoteLockMapImpl implements LockMap, Configurable
47 {
48 private Logger log = LoggerFactory.getLogger(RemoteLockMapImpl.class);
49
50 private static URL lockservlet = null;
51
52
55 private PersistenceBroker getBroker()
56 {
57 return TxManagerFactory.instance().getCurrentTransaction().getBroker();
58 }
59
60
64 public LockEntry getWriter(Object obj)
65 {
66 PersistenceBroker broker = getBroker();
67 Identity oid = new Identity(obj, broker);
68
69 LockEntry result = null;
70 try
71 {
72 result = getWriterRemote(oid);
73 }
74 catch (Throwable e)
75 {
76 log.error(e);
77 }
78 return result;
79 }
80
81 private LockEntry getWriterRemote(Identity oid)
82 throws
83 MalformedURLException ,
84 IOException ,
85 ProtocolException ,
86 ClassNotFoundException
87 {
88 byte selector = (byte) 'w';
89 byte[] requestBarr = buildRequestArray(oid, selector);
90
91 HttpURLConnection conn = getHttpUrlConnection();
92
93 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
95 out.write(requestBarr,0,requestBarr.length);
96 out.flush();
97 out.close();
98
99 InputStream in = conn.getInputStream();
101 ObjectInputStream ois = new ObjectInputStream (in);
102 LockEntry result = (LockEntry) ois.readObject();
103
104 ois.close();
106 conn.disconnect();
107 return result;
108 }
109
110 private HttpURLConnection getHttpUrlConnection()
111 throws MalformedURLException , IOException , ProtocolException
112 {
113 URL lockserver = getLockserverUrl();
114 HttpURLConnection conn= (HttpURLConnection ) lockserver.openConnection();
115
116 conn.setDoInput(true);
117 conn.setDoOutput(true);
118 conn.setRequestMethod("POST");
119 conn.setAllowUserInteraction(false);
120 conn.setUseCaches(false);
121 return conn;
122 }
123
124 private byte[] buildRequestArray(Object object, byte selector) throws IOException
125 {
126 byte[] serialObj = serialize(object);
127 int len = serialObj.length;
128 byte[] requestBarr = new byte[len + 1];
129 requestBarr[0] = selector;
130 System.arraycopy(serialObj,0,requestBarr,1,len);
131 return requestBarr;
132 }
133
134
135 private URL getLockserverUrl() throws MalformedURLException
136 {
137 return lockservlet;
138 }
139
140
141
142
146 public Collection getReaders(Object obj)
147 {
148 Collection result = null;
149 try
150 {
151 Identity oid = new Identity(obj, getBroker());
152 byte selector = (byte) 'r';
153 byte[] requestBarr = buildRequestArray(oid, selector);
154
155 HttpURLConnection conn = getHttpUrlConnection();
156
157 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
159 out.write(requestBarr,0,requestBarr.length);
160 out.flush();
161
162 InputStream in = conn.getInputStream();
164 ObjectInputStream ois = new ObjectInputStream (in);
165 result = (Collection ) ois.readObject();
166
167 ois.close();
169 out.close();
170 conn.disconnect();
171 }
172 catch (Throwable t)
173 {
174 throw new PersistenceBrokerException(t);
175 }
176 return result;
177 }
178
179
180
184 public boolean addReader(TransactionImpl tx, Object obj)
185 {
186 try
187 {
188 LockEntry lock = new LockEntry(new Identity(obj,getBroker()).toString(),
189 tx.getGUID(),
190 System.currentTimeMillis(),
191 LockStrategyFactory.getIsolationLevel(obj),
192 LockEntry.LOCK_READ);
193 addReaderRemote(lock);
194 return true;
195 }
196 catch (Throwable t)
197 {
198 log.error("Cannot store LockEntry for object " + obj + " in transaction " + tx, t);
199 return false;
200 }
201 }
202
203 private void addReaderRemote(LockEntry lock) throws IOException , ClassNotFoundException
204 {
205 byte selector = (byte) 'a';
206 byte[] requestBarr = buildRequestArray(lock,selector);
207
208 HttpURLConnection conn = getHttpUrlConnection();
209
210 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
212 out.write(requestBarr,0,requestBarr.length);
213 out.flush();
214
215 InputStream in = conn.getInputStream();
217 ObjectInputStream ois = new ObjectInputStream (in);
218 Boolean result = (Boolean ) ois.readObject();
219
220 ois.close();
222 out.close();
223 conn.disconnect();
224 if (! result.booleanValue())
225 {
226 throw new PersistenceBrokerException("could not add reader!");
227 }
228 }
229
230 public byte[] serialize(Object obj) throws IOException
231 {
232 ByteArrayOutputStream bao = new ByteArrayOutputStream ();
233 ObjectOutputStream oos = new ObjectOutputStream (bao);
234 oos.writeObject(obj);
235 oos.close();
236 bao.close();
237 byte[] result = bao.toByteArray();
238 return result;
239 }
240
241
245 public void removeReader(TransactionImpl tx, Object obj)
246 {
247 try
248 {
249 LockEntry lock = new LockEntry(new Identity(obj,getBroker()).toString(), tx.getGUID());
250 removeReaderRemote(lock);
251 }
252 catch (Throwable t)
253 {
254 log.error("Cannot remove LockEntry for object " + obj + " in transaction " + tx);
255 }
256 }
257
258 private void removeReaderRemote(LockEntry lock) throws IOException , ClassNotFoundException
259 {
260 byte selector = (byte) 'e';
261 byte[] requestBarr = buildRequestArray(lock,selector);
262
263 HttpURLConnection conn = getHttpUrlConnection();
264
265 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
267 out.write(requestBarr,0,requestBarr.length);
268 out.flush();
269
270 InputStream in = conn.getInputStream();
272 ObjectInputStream ois = new ObjectInputStream (in);
273 Boolean result = (Boolean ) ois.readObject();
274
275 ois.close();
277 out.close();
278 conn.disconnect();
279 if (! result.booleanValue())
280 {
281 throw new PersistenceBrokerException("could not remove reader!");
282 }
283
284 }
285
286
290 public void removeWriter(LockEntry writer)
291 {
292 try
293 {
294 removeWriterRemote(writer);
295 }
296 catch (Throwable t)
297 {
298 log.error("Cannot remove LockEntry", t);
299 }
300 }
301
302 private void removeWriterRemote(LockEntry lock) throws IOException , ClassNotFoundException
303 {
304 byte selector = (byte) 'm';
305 byte[] requestBarr = buildRequestArray(lock,selector);
306
307 HttpURLConnection conn = getHttpUrlConnection();
308
309 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
311 out.write(requestBarr,0,requestBarr.length);
312 out.flush();
313
314 InputStream in = conn.getInputStream();
316 ObjectInputStream ois = new ObjectInputStream (in);
317 Boolean result = (Boolean ) ois.readObject();
318
319 ois.close();
321 out.close();
322 conn.disconnect();
323 if (! result.booleanValue())
324 {
325 throw new PersistenceBrokerException("could not remove writer!");
326 }
327
328 }
329
330
334 public boolean upgradeLock(LockEntry reader)
335 {
336 try
337 {
338 upgradeLockRemote(reader);
339 reader.setLockType(LockEntry.LOCK_WRITE);
340 return true;
341 }
342 catch (Throwable t)
343 {
344 log.error("Cannot upgrade LockEntry " + reader, t);
345 return false;
346 }
347 }
348
349 private void upgradeLockRemote(LockEntry lock) throws IOException , ClassNotFoundException
350 {
351 byte selector = (byte) 'u';
352 byte[] requestBarr = buildRequestArray(lock,selector);
353
354 HttpURLConnection conn = getHttpUrlConnection();
355
356 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
358 out.write(requestBarr,0,requestBarr.length);
359 out.flush();
360
361 InputStream in = conn.getInputStream();
363 ObjectInputStream ois = new ObjectInputStream (in);
364 Boolean result = (Boolean ) ois.readObject();
365
366 ois.close();
368 out.close();
369 conn.disconnect();
370 if (! result.booleanValue())
371 {
372 throw new PersistenceBrokerException("could not remove writer!");
373 }
374
375 }
376
377
381 public boolean setWriter(TransactionImpl tx, Object obj)
382 {
383 try
384 {
385 LockEntry lock = new LockEntry(new Identity(obj,getBroker()).toString(),
386 tx.getGUID(),
387 System.currentTimeMillis(),
388 LockStrategyFactory.getIsolationLevel(obj),
389 LockEntry.LOCK_WRITE);
390
391 setWriterRemote(lock);
392 return true;
393 }
394 catch (Throwable t)
395 {
396 log.error("Cannot set LockEntry for object " + obj + " in transaction " + tx);
397 return false;
398 }
399 }
400
401 private void setWriterRemote(LockEntry lock) throws IOException , ClassNotFoundException
402 {
403 byte selector = (byte) 's';
404 byte[] requestBarr = buildRequestArray(lock,selector);
405
406 HttpURLConnection conn = getHttpUrlConnection();
407
408 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
410 out.write(requestBarr,0,requestBarr.length);
411 out.flush();
412
413 InputStream in = conn.getInputStream();
415 ObjectInputStream ois = new ObjectInputStream (in);
416 Boolean result = (Boolean ) ois.readObject();
417
418 ois.close();
420 out.close();
421 conn.disconnect();
422 if (! result.booleanValue())
423 {
424 throw new PersistenceBrokerException("could not set writer!");
425 }
426
427 }
428
429
433 public boolean hasReadLock(TransactionImpl tx, Object obj)
434 {
435 try
436 {
437 LockEntry lock = new LockEntry(new Identity(obj,getBroker()).toString(), tx.getGUID());
438 boolean result = hasReadLockRemote(lock);
439 return result;
440 }
441 catch (Throwable t)
442 {
443 log.error("Cannot check read lock for object " + obj + " in transaction " + tx, t);
444 return false;
445 }
446 }
447
448 private boolean hasReadLockRemote(LockEntry lock) throws IOException , ClassNotFoundException
449 {
450 byte selector = (byte) 'h';
451 byte[] requestBarr = buildRequestArray(lock,selector);
452
453 HttpURLConnection conn = getHttpUrlConnection();
454
455 BufferedOutputStream out = new BufferedOutputStream (conn.getOutputStream());
457 out.write(requestBarr,0,requestBarr.length);
458 out.flush();
459
460 InputStream in = conn.getInputStream();
462 ObjectInputStream ois = new ObjectInputStream (in);
463 Boolean result = (Boolean ) ois.readObject();
464
465 ois.close();
467 out.close();
468 conn.disconnect();
469 return result.booleanValue();
470 }
471
472
473
474
475
478 public void configure(Configuration pConfig) throws ConfigurationException
479 {
480 String url = pConfig.getString("LockServletUrl","http://127.0.0.1:8080/ojb-lockserver");
481 try
482 {
483 lockservlet = new URL (url);
484 }
485 catch (MalformedURLException e)
486 {
487 throw new ConfigurationException("Invalid LockServlet Url was specified: " + url, e);
488 }
489
490 }
491
492 }
493 |
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