| 1 | /** |
| 2 | * Copyright (C) 2007 NetMind Consulting Bt. |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 3 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with this library; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | */ |
| 18 | |
| 19 | package hu.netmind.beankeeper.lock.impl; |
| 20 | |
| 21 | import hu.netmind.beankeeper.service.StoreContext; |
| 22 | import org.apache.log4j.Logger; |
| 23 | import java.util.*; |
| 24 | import hu.netmind.beankeeper.common.StoreException; |
| 25 | import hu.netmind.beankeeper.event.PersistenceEventListener; |
| 26 | import hu.netmind.beankeeper.event.PersistenceEvent; |
| 27 | import hu.netmind.beankeeper.event.EventDispatcher; |
| 28 | import hu.netmind.beankeeper.node.event.RemoteStateChangeEvent; |
| 29 | import hu.netmind.beankeeper.lock.LockTracker; |
| 30 | import hu.netmind.beankeeper.lock.SessionInfoProvider; |
| 31 | import hu.netmind.beankeeper.lock.SessionInfo; |
| 32 | import hu.netmind.beankeeper.transaction.Transaction; |
| 33 | import hu.netmind.beankeeper.transaction.TransactionTracker; |
| 34 | import hu.netmind.beankeeper.object.PersistenceMetaData; |
| 35 | import hu.netmind.beankeeper.object.ObjectTracker; |
| 36 | import hu.netmind.beankeeper.node.NodeManager; |
| 37 | import hu.netmind.beankeeper.modification.ModificationTracker; |
| 38 | |
| 39 | /** |
| 40 | * This implementation of a lock tracker uses transaction to make a preliminary check |
| 41 | * on the locks, then forwards calls to the central lock tracker. |
| 42 | * @author Brautigam Robert |
| 43 | * @version Revision: $Revision$ |
| 44 | */ |
| 45 | public class LockTrackerImpl implements LockTracker, PersistenceEventListener |
| 46 | { |
| 47 | private static Logger logger = Logger.getLogger(LockTrackerImpl.class); |
| 48 | |
| 49 | private SessionInfoProvider provider; |
| 50 | private EventDispatcher eventDispatcher = null; // Inject |
| 51 | private TransactionTracker transactionTracker = null; // Inject |
| 52 | private ObjectTracker objectTracker = null; // Inject |
| 53 | private NodeManager nodeManager = null; // Inject |
| 54 | private ModificationTracker modificationTracker = null; // Injected |
| 55 | |
| 56 | public void init(Map parameters) |
| 57 | { |
| 58 | this.provider=new TransactionInfoProvider(transactionTracker); |
| 59 | eventDispatcher.registerListener(this); |
| 60 | } |
| 61 | |
| 62 | public void release() |
| 63 | { |
| 64 | eventDispatcher.unregisterListener(this); |
| 65 | } |
| 66 | |
| 67 | public SessionInfoProvider getProvider() |
| 68 | { |
| 69 | return provider; |
| 70 | } |
| 71 | public void setProvider(SessionInfoProvider provider) |
| 72 | { |
| 73 | this.provider=provider; |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Lock a single object, and ensure that the object given is the |
| 78 | * most recent version of the object. The session information is gathered |
| 79 | * from the session info provider. |
| 80 | * @throws ConcurrentModificationException If the object is already |
| 81 | * locked by another thread. |
| 82 | */ |
| 83 | public void lockEnsureCurrent(Object obj) |
| 84 | { |
| 85 | lock(new Object[] { obj },null,-1, true, false); |
| 86 | } |
| 87 | |
| 88 | /** |
| 89 | * Lock a single object. The session information is gathered |
| 90 | * from the session info provider. |
| 91 | * @throws ConcurrentModificationException If the object is already |
| 92 | * locked by another thread. |
| 93 | */ |
| 94 | public void lock(Object obj) |
| 95 | { |
| 96 | lock(new Object[] { obj },null,-1, false, false); |
| 97 | } |
| 98 | |
| 99 | /** |
| 100 | * Lock a single object, and guarantee it's current. |
| 101 | * The session information is gathered from the session info provider. |
| 102 | * @param obj The object to lock. |
| 103 | * @param wait Wait the given amount of milliseconds for the lock to |
| 104 | * free up. Method only throws ConcurrentModificationException if |
| 105 | * the lock is not available in the given time. |
| 106 | * @throws ConcurrentModificationException If the object is already |
| 107 | * locked by another thread. |
| 108 | */ |
| 109 | public void lockEnsureCurrent(Object obj,int wait) |
| 110 | { |
| 111 | lock(new Object[] { obj },null,wait, true, false); |
| 112 | } |
| 113 | |
| 114 | /** |
| 115 | * Lock a single object with wait period given. The session information is gathered |
| 116 | * from the session info provider. |
| 117 | * @param obj The object to lock. |
| 118 | * @param wait Wait the given amount of milliseconds for the lock to |
| 119 | * free up. Method only throws ConcurrentModificationException if |
| 120 | * the lock is not available in the given time. |
| 121 | * @throws ConcurrentModificationException If the object is already |
| 122 | * locked by another thread. |
| 123 | */ |
| 124 | public void lock(Object obj,int wait) |
| 125 | { |
| 126 | lock(new Object[] { obj },null,wait, false, false); |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * Lock a single object with the session information given, |
| 131 | * and check is the given object is the current version. |
| 132 | * @throws ConcurrentModificationException If the object is already |
| 133 | * locked by another thread. |
| 134 | */ |
| 135 | public void lockEnsureCurrent(Object obj, SessionInfo info) |
| 136 | { |
| 137 | lock(new Object[] { obj }, info, -1, true, false); |
| 138 | } |
| 139 | |
| 140 | /** |
| 141 | * Lock a single object with the session information given. |
| 142 | * @throws ConcurrentModificationException If the object is already |
| 143 | * locked by another thread. |
| 144 | */ |
| 145 | public void lock(Object obj, SessionInfo info) |
| 146 | { |
| 147 | lock(new Object[] { obj }, info, -1, false, false); |
| 148 | } |
| 149 | |
| 150 | /** |
| 151 | * Lock multiple objects, and check whether given objects |
| 152 | * are current. The session information is gathered |
| 153 | * from the session info provider. Use this method, if you want |
| 154 | * to lock multiple objects at the same time. |
| 155 | * @throws ConcurrentModificationException If the object is already |
| 156 | * locked by another thread. |
| 157 | */ |
| 158 | public void lockEnsureCurrent(Object[] objs) |
| 159 | { |
| 160 | lock(objs,null,-1, true, false); |
| 161 | } |
| 162 | |
| 163 | /** |
| 164 | * Lock multiple objects. The session information is gathered |
| 165 | * from the session info provider. Use this method, if you want |
| 166 | * to lock multiple objects at the same time. |
| 167 | * @throws ConcurrentModificationException If the object is already |
| 168 | * locked by another thread. |
| 169 | */ |
| 170 | public void lock(Object[] objs) |
| 171 | { |
| 172 | lock(objs,null,-1, false, false); |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * Lock multiple objects, and check whether given objects |
| 177 | * are current. The session information is gathered |
| 178 | * from the session info provider. Use this method, if you want |
| 179 | * to lock multiple objects at the same time. |
| 180 | * @param wait Wait the given amount of milliseconds for the lock to |
| 181 | * free up. Method only throws ConcurrentModificationException if |
| 182 | * the lock is not available in the given time. |
| 183 | * @throws ConcurrentModificationException If the object is already |
| 184 | * locked by another thread. |
| 185 | */ |
| 186 | public void lockEnsureCurrent(Object[] objs, int wait) |
| 187 | { |
| 188 | lock(objs,null,wait,true, false); |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Lock multiple objects. The session information is gathered |
| 193 | * from the session info provider. Use this method, if you want |
| 194 | * to lock multiple objects at the same time. |
| 195 | * @param wait Wait the given amount of milliseconds for the lock to |
| 196 | * free up. Method only throws ConcurrentModificationException if |
| 197 | * the lock is not available in the given time. |
| 198 | * @throws ConcurrentModificationException If the object is already |
| 199 | * locked by another thread. |
| 200 | */ |
| 201 | public void lock(Object[] objs, int wait) |
| 202 | { |
| 203 | lock(objs,null,wait,false, false); |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * Lock a single object read-only, and ensure that the object given is the |
| 208 | * most recent version of the object. The session information is gathered |
| 209 | * from the session info provider. |
| 210 | * @throws ConcurrentModificationException If the object is already |
| 211 | * locked by another thread. |
| 212 | */ |
| 213 | public void lockReadOnlyEnsureCurrent(Object obj) |
| 214 | { |
| 215 | lock(new Object[] { obj },null,-1, true, true); |
| 216 | } |
| 217 | |
| 218 | /** |
| 219 | * Lock a single object read-only. The session information is gathered |
| 220 | * from the session info provider. |
| 221 | * @throws ConcurrentModificationException If the object is already |
| 222 | * locked by another thread. |
| 223 | */ |
| 224 | public void lockReadOnly(Object obj) |
| 225 | { |
| 226 | lock(new Object[] { obj },null,-1, false, true); |
| 227 | } |
| 228 | |
| 229 | /** |
| 230 | * Lock a single object read-only, and guarantee it's current. |
| 231 | * The session information is gathered from the session info provider. |
| 232 | * @param obj The object to lock. |
| 233 | * @param wait Wait the given amount of milliseconds for the lock to |
| 234 | * free up. Method only throws ConcurrentModificationException if |
| 235 | * the lock is not available in the given time. |
| 236 | * @throws ConcurrentModificationException If the object is already |
| 237 | * locked by another thread. |
| 238 | */ |
| 239 | public void lockReadOnlyEnsureCurrent(Object obj,int wait) |
| 240 | { |
| 241 | lock(new Object[] { obj },null,wait, true, true); |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * Lock a single object read-only with wait period given. The session information is gathered |
| 246 | * from the session info provider. |
| 247 | * @param obj The object to lock. |
| 248 | * @param wait Wait the given amount of milliseconds for the lock to |
| 249 | * free up. Method only throws ConcurrentModificationException if |
| 250 | * the lock is not available in the given time. |
| 251 | * @throws ConcurrentModificationException If the object is already |
| 252 | * locked by another thread. |
| 253 | */ |
| 254 | public void lockReadOnly(Object obj,int wait) |
| 255 | { |
| 256 | lock(new Object[] { obj },null,wait, false, true); |
| 257 | } |
| 258 | |
| 259 | /** |
| 260 | * Lock a single object read-only with the session information given, |
| 261 | * and check is the given object is the current version. |
| 262 | * @throws ConcurrentModificationException If the object is already |
| 263 | * locked by another thread. |
| 264 | */ |
| 265 | public void lockReadOnlyEnsureCurrent(Object obj, SessionInfo info) |
| 266 | { |
| 267 | lock(new Object[] { obj }, info, -1, true, true); |
| 268 | } |
| 269 | |
| 270 | /** |
| 271 | * Lock a single object read-only with the session information given. |
| 272 | * @throws ConcurrentModificationException If the object is already |
| 273 | * locked by another thread. |
| 274 | */ |
| 275 | public void lockReadOnly(Object obj, SessionInfo info) |
| 276 | { |
| 277 | lock(new Object[] { obj }, info, -1, false, true); |
| 278 | } |
| 279 | |
| 280 | /** |
| 281 | * Lock multiple objects read-only, and check whether given objects |
| 282 | * are current. The session information is gathered |
| 283 | * from the session info provider. Use this method, if you want |
| 284 | * to lock multiple objects at the same time. |
| 285 | * @throws ConcurrentModificationException If the object is already |
| 286 | * locked by another thread. |
| 287 | */ |
| 288 | public void lockReadOnlyEnsureCurrent(Object[] objs) |
| 289 | { |
| 290 | lock(objs,null,-1, true, true); |
| 291 | } |
| 292 | |
| 293 | /** |
| 294 | * Lock multiple objects read-only. The session information is gathered |
| 295 | * from the session info provider. Use this method, if you want |
| 296 | * to lock multiple objects at the same time. |
| 297 | * @throws ConcurrentModificationException If the object is already |
| 298 | * locked by another thread. |
| 299 | */ |
| 300 | public void lockReadOnly(Object[] objs) |
| 301 | { |
| 302 | lock(objs,null,-1, false, true); |
| 303 | } |
| 304 | |
| 305 | /** |
| 306 | * Lock multiple objects read-only, and check whether given objects |
| 307 | * are current. The session information is gathered |
| 308 | * from the session info provider. Use this method, if you want |
| 309 | * to lock multiple objects at the same time. |
| 310 | * @param wait Wait the given amount of milliseconds for the lock to |
| 311 | * free up. Method only throws ConcurrentModificationException if |
| 312 | * the lock is not available in the given time. |
| 313 | * @throws ConcurrentModificationException If the object is already |
| 314 | * locked by another thread. |
| 315 | */ |
| 316 | public void lockReadOnlyEnsureCurrent(Object[] objs, int wait) |
| 317 | { |
| 318 | lock(objs,null,wait,true, true); |
| 319 | } |
| 320 | |
| 321 | /** |
| 322 | * Lock multiple objects read-only. The session information is gathered |
| 323 | * from the session info provider. Use this method, if you want |
| 324 | * to lock multiple objects at the same time. |
| 325 | * @param wait Wait the given amount of milliseconds for the lock to |
| 326 | * free up. Method only throws ConcurrentModificationException if |
| 327 | * the lock is not available in the given time. |
| 328 | * @throws ConcurrentModificationException If the object is already |
| 329 | * locked by another thread. |
| 330 | */ |
| 331 | public void lockReadOnly(Object[] objs, int wait) |
| 332 | { |
| 333 | lock(objs,null,wait,false, true); |
| 334 | } |
| 335 | |
| 336 | /** |
| 337 | * Lock multiple objects with all possible parameters specified. |
| 338 | * Use this method, if you want to lock multiple objects at the same time. |
| 339 | * If classes are asked to be ensured to be current, the following date is |
| 340 | * taken into account: |
| 341 | * <ul> |
| 342 | * <li>If the lock is called from inside a transaction, the |
| 343 | * transaction's first operation's date is taken.</li> |
| 344 | * <li>If there are regular objects with this lock call, then |
| 345 | * the oldest object's read date is taken.</li> |
| 346 | * </ul> |
| 347 | * Whichever was earlier, the classes are checked against that date. |
| 348 | * @param objs The object to lock simultaniously. |
| 349 | * @param info The session info to memorize for this lock. This object will |
| 350 | * be included in the ConcurrentModificationException. |
| 351 | * @param wait Wait the given amount of milliseconds for the lock to |
| 352 | * free up. Method only throws ConcurrentModificationException if |
| 353 | * the lock is not available in the given time. |
| 354 | * @param ensureCurrent Do the objects need to be guaranteed to be current. |
| 355 | * If this flag is set, the lock operation will fail, if any supplied |
| 356 | * object has a newer version. |
| 357 | * @param readOnly Whether the lock should be read-only. If a lock is read-only, then |
| 358 | * other read-only locks can still be established on the specified objects, read-write |
| 359 | * locks will however fail. |
| 360 | * @throws ConcurrentModificationException If the object is already |
| 361 | * locked by another process. |
| 362 | */ |
| 363 | public synchronized void lock(Object[] objs, SessionInfo info, int wait, boolean ensureCurrent, boolean readOnly) |
| 364 | { |
| 365 | if ( logger.isDebugEnabled() ) |
| 366 | logger.debug("locking "+objs.length+" objects, info: "+info+", wait: "+wait); |
| 367 | // Allocate session info |
| 368 | if ( info == null ) |
| 369 | { |
| 370 | info = new SessionInfo(); // Empty |
| 371 | try |
| 372 | { |
| 373 | if ( provider != null ) |
| 374 | info = provider.getSessionInfo(); |
| 375 | } catch ( Throwable e ) { |
| 376 | logger.warn("could not allocate session info from provider",e); |
| 377 | } |
| 378 | } |
| 379 | // If this lock operation is inside a transacion, |
| 380 | // then the start of the transaction will be the |
| 381 | // date the classes (tables) are ensure to be current. |
| 382 | // So if inside a transaction a class is asked to be |
| 383 | // ensured actual, then it's ensured that it's not |
| 384 | // been tampered with since the beginning of the transacion. |
| 385 | Transaction tx = transactionTracker.getTransaction( |
| 386 | TransactionTracker.TX_OPTIONAL); |
| 387 | Long firstSerial = null; |
| 388 | long txSerial = 0; |
| 389 | if ( tx != null ) |
| 390 | { |
| 391 | firstSerial = tx.getSerial(); |
| 392 | logger.debug("there was a transaction, classes will be compared to at least: "+firstSerial); |
| 393 | if ( tx.getSerial() != null ) |
| 394 | txSerial = tx.getSerial().longValue(); |
| 395 | } |
| 396 | // Create metadata for all objects |
| 397 | ArrayList remoteLockMetas = new ArrayList(); |
| 398 | for ( int i=0; i<objs.length; i++ ) |
| 399 | { |
| 400 | LockMetaData meta = new LockMetaData(); |
| 401 | if ( objs[i] instanceof Class ) |
| 402 | { |
| 403 | // Classes |
| 404 | meta.setObjectClass((Class)objs[i]); |
| 405 | } else { |
| 406 | // Objects |
| 407 | meta.setObjectClass(objs[i].getClass()); |
| 408 | PersistenceMetaData persistenceMeta = objectTracker.getMetaData(objs[i]); |
| 409 | meta.setPersistenceId(persistenceMeta.getPersistenceId()); |
| 410 | meta.setLastCurrentSerial(persistenceMeta.getLastCurrentSerial()); |
| 411 | meta.setPersistenceStart(persistenceMeta.getPersistenceStart()); |
| 412 | meta.setPersistenceEnd(persistenceMeta.getPersistenceEnd()); |
| 413 | // Check if this query serial is older than the first date current |
| 414 | if ( (meta.getLastCurrentSerial()!=null) && ((firstSerial==null) || (firstSerial.longValue() > meta.getLastCurrentSerial().longValue())) ) |
| 415 | firstSerial = meta.getLastCurrentSerial(); |
| 416 | } |
| 417 | remoteLockMetas.add(meta); |
| 418 | } |
| 419 | // Re-set the oldest serial to the class-only metas |
| 420 | for ( int i=0; i<remoteLockMetas.size(); i++ ) |
| 421 | { |
| 422 | LockMetaData meta = (LockMetaData) remoteLockMetas.get(i); |
| 423 | if ( meta.getPersistenceId() == null ) |
| 424 | meta.setLastCurrentSerial(firstSerial); |
| 425 | } |
| 426 | // Now make an ordered list of the remote lock objects. It should be |
| 427 | // ordered, because that reduces the likelyhood of a deadlock. |
| 428 | Collections.sort(remoteLockMetas); |
| 429 | // Lock with central lock tracker |
| 430 | SessionInfo oldInfo = lock(nodeManager.getId(), |
| 431 | Thread.currentThread().getId(),txSerial,remoteLockMetas,info,wait,ensureCurrent,readOnly); |
| 432 | if ( oldInfo != null ) |
| 433 | throw new hu.netmind.beankeeper.lock.ConcurrentModificationException(oldInfo,objs,"Tried to lock, but was already locked."); |
| 434 | // If object could be locked, and it ensured that those objects |
| 435 | // were current, then set the last known current serial to current |
| 436 | if ( tx != null ) |
| 437 | { |
| 438 | Long serial = tx.getSerial(); |
| 439 | for ( int i=0; i<objs.length; i++ ) |
| 440 | { |
| 441 | if ( objs[i] instanceof Class ) |
| 442 | continue; |
| 443 | objectTracker.updateCurrent(objs[i],serial); |
| 444 | } |
| 445 | } |
| 446 | // All is good in lockworld |
| 447 | logger.debug("successful lock operation."); |
| 448 | } |
| 449 | |
| 450 | /** |
| 451 | * Unlock a single object. If the object is not locked, nothing is done. |
| 452 | */ |
| 453 | public void unlock(Object obj) |
| 454 | { |
| 455 | unlock(new Object[] { obj }); |
| 456 | } |
| 457 | |
| 458 | /** |
| 459 | * Unlock multiple objects. |
| 460 | */ |
| 461 | public synchronized void unlock(Object[] objs) |
| 462 | { |
| 463 | if ( logger.isDebugEnabled() ) |
| 464 | logger.debug("unlocking "+objs.length+" objects."); |
| 465 | // The transaction if there is any |
| 466 | Transaction tx = transactionTracker.getTransaction( |
| 467 | TransactionTracker.TX_OPTIONAL); |
| 468 | long txSerial = 0; |
| 469 | if ( (tx!=null) && (tx.getSerial()!=null) ) |
| 470 | txSerial = tx.getSerial().longValue(); |
| 471 | // Go through all objects and create lock metadata |
| 472 | ArrayList remoteLockMetas = new ArrayList(); |
| 473 | for ( int i=0; i<objs.length; i++ ) |
| 474 | { |
| 475 | LockMetaData meta = new LockMetaData(); |
| 476 | if ( objs[i] instanceof Class ) |
| 477 | { |
| 478 | // Classes |
| 479 | meta.setObjectClass((Class)objs[i]); |
| 480 | } else { |
| 481 | // Objects |
| 482 | meta.setObjectClass(objs[i].getClass()); |
| 483 | PersistenceMetaData persistenceMeta = objectTracker.getMetaData(objs[i]); |
| 484 | meta.setPersistenceId(persistenceMeta.getPersistenceId()); |
| 485 | } |
| 486 | remoteLockMetas.add(meta); |
| 487 | } |
| 488 | // Remote unlock |
| 489 | try |
| 490 | { |
| 491 | unlock(nodeManager.getId(), |
| 492 | Thread.currentThread().getId(),txSerial,remoteLockMetas); |
| 493 | } catch ( Exception e ) { |
| 494 | // Do not throw excetion here, because unlock only fails, |
| 495 | // if connection is severed, in which case the server will |
| 496 | // invalidate all locks either way. |
| 497 | logger.warn("could not unlock remotely",e); |
| 498 | } |
| 499 | } |
| 500 | |
| 501 | /* |
| 502 | * Remote part of the service. |
| 503 | * Tracks remote locks. There are two views of tracked data: the index |
| 504 | * of the node it came from, and the object's id itself. There is also |
| 505 | * a transaction associated with the lock. |
| 506 | */ |
| 507 | private HashMap lockEntriesByName; |
| 508 | private HashMap lockEntriesByIndex; |
| 509 | private HashMap indirectLockEntriesByClass; |
| 510 | |
| 511 | public LockTrackerImpl() |
| 512 | { |
| 513 | lockEntriesByName = new HashMap(); |
| 514 | lockEntriesByIndex = new HashMap(); |
| 515 | indirectLockEntriesByClass = new HashMap(); |
| 516 | } |
| 517 | |
| 518 | private void modifyIndirectEntries(LockEntry entry, boolean add) |
| 519 | { |
| 520 | modifyIndirectEntries(entry.objectClass,entry,add); |
| 521 | } |
| 522 | |
| 523 | private void modifyIndirectEntries(Class currentClass, LockEntry entry, boolean add) |
| 524 | { |
| 525 | // If there is no class, then return |
| 526 | if ( currentClass == null ) |
| 527 | return; |
| 528 | // Mark class |
| 529 | Set entries = (Set) indirectLockEntriesByClass.get(currentClass); |
| 530 | if ( entries == null ) |
| 531 | { |
| 532 | entries = new HashSet(); |
| 533 | indirectLockEntriesByClass.put(currentClass,entries); |
| 534 | } |
| 535 | if ( add ) |
| 536 | { |
| 537 | // Add entry to indicate that it indirectly uses this class |
| 538 | entries.add(entry); |
| 539 | } else { |
| 540 | // Remove that entry |
| 541 | entries.remove(entry); |
| 542 | if ( entries.size() == 0 ) |
| 543 | indirectLockEntriesByClass.remove(currentClass); |
| 544 | } |
| 545 | // Mark superclass |
| 546 | modifyIndirectEntries(currentClass.getSuperclass(),entry,add); |
| 547 | // Mark interfaces |
| 548 | Class[] interfaces = currentClass.getInterfaces(); |
| 549 | for ( int i=0; i<interfaces.length; i++ ) |
| 550 | modifyIndirectEntries(interfaces[i],entry,add); |
| 551 | } |
| 552 | |
| 553 | public void handle(PersistenceEvent event) |
| 554 | { |
| 555 | if ( event instanceof RemoteStateChangeEvent ) |
| 556 | unlockAll(((RemoteStateChangeEvent)event).getNodeId()); |
| 557 | } |
| 558 | |
| 559 | private synchronized void unlockAll(int index) |
| 560 | { |
| 561 | if ( logger.isDebugEnabled() ) |
| 562 | logger.debug("unlocking all from: "+index); |
| 563 | Set entries = (Set) lockEntriesByIndex.remove(new Integer(index)); |
| 564 | if ( entries == null ) |
| 565 | return; |
| 566 | Iterator entriesIterator = entries.iterator(); |
| 567 | while ( entriesIterator.hasNext() ) |
| 568 | { |
| 569 | LockEntry entry = (LockEntry) entriesIterator.next(); |
| 570 | Set nameEntries = (Set) lockEntriesByName.get(entry.name); |
| 571 | if ( nameEntries != null ) |
| 572 | { |
| 573 | nameEntries.remove(entry); |
| 574 | if ( nameEntries.isEmpty() ) |
| 575 | lockEntriesByName.remove(entry.name); |
| 576 | } |
| 577 | modifyIndirectEntries(entry,false); |
| 578 | } |
| 579 | // Notify waiting threads, that locks became unlocked. |
| 580 | notifyAll(); |
| 581 | } |
| 582 | |
| 583 | /** |
| 584 | * Wait a given amount of time for an unlock event. |
| 585 | * @return The new wait interval that's left of the input wait period, or -1 if during |
| 586 | * the wait period no unlock events were generated. |
| 587 | */ |
| 588 | private int waitForUnlock(int wait) |
| 589 | { |
| 590 | if ( wait < 0 ) |
| 591 | throw new StoreException("wait called with negative wit period, this should not happen"); |
| 592 | // Start wait |
| 593 | long startTime = System.currentTimeMillis(); |
| 594 | try |
| 595 | { |
| 596 | // Wait for unlock notification |
| 597 | if ( wait > 0 ) |
| 598 | wait(wait); |
| 599 | else |
| 600 | wait(); |
| 601 | } catch ( Throwable e ) { |
| 602 | throw new StoreException("wait interrupted",e); |
| 603 | } |
| 604 | if ( wait > 0 ) |
| 605 | { |
| 606 | long endTime = System.currentTimeMillis(); |
| 607 | wait -= (endTime-startTime); |
| 608 | if ( wait <= 0 ) // Would mean infinite |
| 609 | wait = -1; // Expired instead |
| 610 | } |
| 611 | // Return the modified time |
| 612 | return wait; |
| 613 | } |
| 614 | |
| 615 | /** |
| 616 | * Get the lock entries for a class or any of it's superclasses or superinterfaces. |
| 617 | */ |
| 618 | private Set getClassLockEntry(Class currentClass) |
| 619 | { |
| 620 | if ( currentClass == null ) |
| 621 | return null; |
| 622 | logger.debug("checking lock entry for class: "+currentClass); |
| 623 | // Check class |
| 624 | Set result = new HashSet(); |
| 625 | Set entries = (Set) lockEntriesByName.get(currentClass.getName()); |
| 626 | if ( entries != null ) |
| 627 | result.addAll(entries); |
| 628 | // Check superclass |
| 629 | entries = getClassLockEntry(currentClass.getSuperclass()); |
| 630 | if ( entries != null ) |
| 631 | result.addAll(entries); |
| 632 | // Check interfaces |
| 633 | Class[] interfaces = currentClass.getInterfaces(); |
| 634 | for ( int i=0; i<interfaces.length; i++ ) |
| 635 | { |
| 636 | entries = getClassLockEntry(interfaces[i]); |
| 637 | if ( entries != null ) |
| 638 | result.addAll(entries); |
| 639 | } |
| 640 | // Fallback |
| 641 | return result; |
| 642 | } |
| 643 | |
| 644 | /** |
| 645 | * Get the composite name for a lock metadata. |
| 646 | */ |
| 647 | private String getEntryName(LockMetaData meta) |
| 648 | { |
| 649 | return meta.getObjectClass().getName()+(meta.getPersistenceId()==null?"":(":"+meta.getPersistenceId())); |
| 650 | } |
| 651 | |
| 652 | private SessionInfo lock(int index, long threadId, long txSerial, LockMetaData meta, SessionInfo info, int wait, boolean ensureCurrent, boolean readOnly) |
| 653 | { |
| 654 | if ( logger.isDebugEnabled() ) |
| 655 | logger.debug("locking from: "+index+":"+threadId+":"+txSerial+", meta: "+meta+", info: "+info+", wait: "+wait+", ensure current: "+ensureCurrent); |
| 656 | // Check whether object can have a lock engaged. To do this we require the |
| 657 | // following checks _in a single interation_, because if we yield to another |
| 658 | // thread, the situation may change, and every check has to be made again. |
| 659 | // The checks: |
| 660 | // - Check if lock is explicitly given using lockEntriesByName (if object) |
| 661 | // - Check if lock explicitly set for any class or superclass. |
| 662 | // - Check whether class has implicit usage by other lock (if class). |
| 663 | boolean allChecksOk = false; |
| 664 | LockEntry ownedEntry = null; |
| 665 | while ( ! allChecksOk ) |
| 666 | { |
| 667 | LockEntry lockingEntry = null; |
| 668 | // Check whether object is locked |
| 669 | if ( meta.getPersistenceId() != null ) |
| 670 | { |
| 671 | Set entries = (Set) lockEntriesByName.get(getEntryName(meta)); |
| 672 | if ( (entries!=null) && (!entries.isEmpty()) ) |
| 673 | { |
| 674 | Iterator entriesIterator = entries.iterator(); |
| 675 | while ( (entriesIterator.hasNext()) && (lockingEntry==null) ) |
| 676 | { |
| 677 | LockEntry entry = (LockEntry) entriesIterator.next(); |
| 678 | if ( (entry.index == index) && (entry.threadId==threadId) && |
| 679 | ((entry.txSerial==0) || (txSerial==0) || (entry.txSerial==txSerial)) ) |
| 680 | { |
| 681 | ownedEntry = entry; |
| 682 | } else { |
| 683 | if ( (!readOnly) || (!entry.readOnly) ) |
| 684 | { |
| 685 | logger.debug("lock is present from another node or thread, and either that or this lock should be exclusive, lock unsuccessful."); |
| 686 | lockingEntry = entry; |
| 687 | } |
| 688 | } |
| 689 | } |
| 690 | } else { |
| 691 | logger.debug("no lock for object is present."); |
| 692 | } |
| 693 | } |
| 694 | // Check class and superclasses, whether they are locked |
| 695 | if ( lockingEntry == null ) |
| 696 | { |
| 697 | Set entries = getClassLockEntry(meta.getObjectClass()); |
| 698 | Iterator entriesIterator = entries.iterator(); |
| 699 | while ( (entriesIterator.hasNext()) && (lockingEntry==null) ) |
| 700 | { |
| 701 | LockEntry entry = (LockEntry) entriesIterator.next(); |
| 702 | if ((! ( (entry.index == index) && (entry.threadId==threadId) && |
| 703 | ((entry.txSerial==0) || (txSerial==0) || (entry.txSerial==txSerial)) ) ) && |
| 704 | (!(entry.readOnly && readOnly)) ) |
| 705 | lockingEntry = entry; |
| 706 | } |
| 707 | } |
| 708 | // If this is a class, then check, if it's indirectly used by |
| 709 | // already activated locks, which are not owned by this thread. |
| 710 | if ( (lockingEntry==null) && (meta.getPersistenceId() == null) ) |
| 711 | { |
| 712 | Set entries = (Set) indirectLockEntriesByClass.get(meta.getObjectClass()); |
| 713 | if ( entries != null ) |
| 714 | { |
| 715 | Iterator entriesIterator = entries.iterator(); |
| 716 | while ( (lockingEntry==null) && (entriesIterator.hasNext())) |
| 717 | { |
| 718 | LockEntry entry = (LockEntry) entriesIterator.next(); |
| 719 | if ((! ( (entry.index == index) && (entry.threadId==threadId) && |
| 720 | ((entry.txSerial==0) || (txSerial==0) || (entry.txSerial==txSerial)) ) ) && |
| 721 | (!(entry.readOnly && readOnly)) ) |
| 722 | lockingEntry = entry; |
| 723 | } |
| 724 | } |
| 725 | } |
| 726 | // If a locking entry is found, then try to wait |
| 727 | if ( lockingEntry != null ) |
| 728 | { |
| 729 | if ( wait < 0 ) |
| 730 | { |
| 731 | // Tried to lock from another node or another thread in the same node |
| 732 | logger.debug("object already locked: "+getEntryName(meta)+", from: "+lockingEntry.index+":"+lockingEntry.threadId+":"+lockingEntry.txSerial); |
| 733 | return lockingEntry.info; |
| 734 | } else { |
| 735 | // Wait for an unlock event |
| 736 | wait = waitForUnlock(wait); |
| 737 | } |
| 738 | allChecksOk = false; |
| 739 | } else { |
| 740 | allChecksOk = true; |
| 741 | } |
| 742 | } |
| 743 | // The lock is ready to be engaged. Now we check (if necessary) |
| 744 | // if the object is current. If it is not, we can still throw |
| 745 | // an exception, because the lock is not yet inserted in the |
| 746 | // datamodel. On the other hand, the object is surely not locked, |
| 747 | // or owned by caller, so it's sure, there won't be any operations |
| 748 | // on the object now, during this call. |
| 749 | if ( ensureCurrent ) |
| 750 | { |
| 751 | boolean current = false; |
| 752 | if ( meta.getPersistenceId()==null ) |
| 753 | { |
| 754 | // This means target is a class |
| 755 | current = modificationTracker.isCurrent( |
| 756 | meta.getObjectClass(),meta.getLastCurrentSerial()); |
| 757 | } else { |
| 758 | // Meta describes an object |
| 759 | current = modificationTracker.isCurrent(meta); |
| 760 | } |
| 761 | if ( ! current ) |
| 762 | { |
| 763 | logger.debug("object was not current, returning session"); |
| 764 | return new SessionInfo(); // Return empty session info |
| 765 | } |
| 766 | } |
| 767 | // If entry is already present, then just adjust |
| 768 | if ( ownedEntry != null ) |
| 769 | { |
| 770 | if ( logger.isDebugEnabled() ) |
| 771 | logger.debug("there is already a lock for that object, but from the same node"+ |
| 772 | " and thread, and no other locks (or just read-only locks) present, lock success."); |
| 773 | // Lock comes from the same node, and from the same thread, |
| 774 | // so it's the owner of the lock. Increase depth level. |
| 775 | ownedEntry.lockDepth++; |
| 776 | // Adjust readonly flag |
| 777 | ownedEntry.readOnly &= readOnly; |
| 778 | return null; |
| 779 | } |
| 780 | // Create lock |
| 781 | LockEntry entry = new LockEntry(); |
| 782 | entry.id=meta.getPersistenceId(); |
| 783 | entry.objectClass=meta.getObjectClass(); |
| 784 | entry.name=getEntryName(meta); |
| 785 | entry.index=index; |
| 786 | entry.threadId=threadId; |
| 787 | entry.txSerial=txSerial; |
| 788 | entry.info=info; |
| 789 | entry.lockDepth=1; |
| 790 | entry.readOnly=readOnly; |
| 791 | entry.lastModificationTime=System.currentTimeMillis(); |
| 792 | // Update data model |
| 793 | Set entries = (Set) lockEntriesByIndex.get(new Integer(index)); |
| 794 | if ( entries == null ) |
| 795 | { |
| 796 | entries = new HashSet(); |
| 797 | lockEntriesByIndex.put(new Integer(index),entries); |
| 798 | } |
| 799 | entries.add(entry); |
| 800 | Set nameEntries = (Set) lockEntriesByName.get(getEntryName(meta)); |
| 801 | if ( nameEntries == null ) |
| 802 | { |
| 803 | nameEntries = new HashSet(); |
| 804 | lockEntriesByName.put(getEntryName(meta),nameEntries); |
| 805 | } |
| 806 | nameEntries.add(entry); |
| 807 | modifyIndirectEntries(entry,true); |
| 808 | // Return |
| 809 | logger.debug("new lock successfully created"); |
| 810 | return null; |
| 811 | } |
| 812 | |
| 813 | private void unlock(int index, long threadId, long txSerial, LockMetaData meta) |
| 814 | { |
| 815 | if ( logger.isDebugEnabled() ) |
| 816 | logger.debug("unlocking from: "+index+":"+threadId+":"+txSerial+", name: "+getEntryName(meta)); |
| 817 | // Get the entry first. Note: owner is the same |
| 818 | // if it's the same index and thread. Transactions do not matter here. |
| 819 | Set nameEntries = (Set) lockEntriesByName.get(getEntryName(meta)); |
| 820 | LockEntry entry = null; |
| 821 | if ( nameEntries != null ) |
| 822 | { |
| 823 | Iterator nameEntriesIterator = nameEntries.iterator(); |
| 824 | while ( (nameEntriesIterator.hasNext()) && (entry==null) ) |
| 825 | { |
| 826 | LockEntry tmp = (LockEntry) nameEntriesIterator.next(); |
| 827 | if ( (tmp.index==index) && (tmp.threadId==threadId) ) |
| 828 | entry=tmp; |
| 829 | } |
| 830 | } |
| 831 | // Check if it's there |
| 832 | if ( entry == null ) |
| 833 | { |
| 834 | logger.warn("unlocking from: "+index+":"+threadId+":"+txSerial+", name: "+getEntryName(meta)); |
| 835 | logger.warn("no lock present, altough tried to unlock, possible unbalanced lock-unlock in code."); |
| 836 | return; // No lock present |
| 837 | } |
| 838 | // Decrease lock depth |
| 839 | entry.lockDepth--; |
| 840 | if ( entry.lockDepth > 0 ) |
| 841 | { |
| 842 | logger.debug("lock depth decreased to: "+entry.lockDepth); |
| 843 | return; // No unlock yet |
| 844 | } |
| 845 | // Full remove of the entry |
| 846 | Set entries = (Set) lockEntriesByIndex.get(new Integer(index)); |
| 847 | if ( entries == null ) |
| 848 | return; |
| 849 | entries.remove(entry); |
| 850 | if ( entries.size() == 0 ) |
| 851 | lockEntriesByIndex.remove(new Integer(index)); |
| 852 | nameEntries.remove(entry); |
| 853 | if ( nameEntries.isEmpty() ) |
| 854 | lockEntriesByName.remove(getEntryName(meta)); |
| 855 | modifyIndirectEntries(entry,false); |
| 856 | logger.debug("successful unlock operation"); |
| 857 | } |
| 858 | |
| 859 | /** |
| 860 | * Lock given ids. |
| 861 | */ |
| 862 | public synchronized SessionInfo lock(int index, long threadId, long txSerial, |
| 863 | List metas, SessionInfo info, int wait, boolean ensureCurrent, boolean readOnly) |
| 864 | { |
| 865 | // Make it a server call |
| 866 | if ( nodeManager.getRole() == NodeManager.NodeRole.CLIENT ) |
| 867 | { |
| 868 | logger.debug("lock on client, sending to server"); |
| 869 | return (SessionInfo) nodeManager.callServer(LockTracker.class.getName(), |
| 870 | "lock",new Class[] { int.class, long.class, long.class, |
| 871 | List.class, SessionInfo.class, int.class, boolean.class, boolean.class }, |
| 872 | new Object[] { index, threadId, txSerial, metas, info, wait, ensureCurrent, readOnly }); |
| 873 | } |
| 874 | // Local |
| 875 | ArrayList lockedMetas = new ArrayList(); |
| 876 | // Go through all ids, and lock'em all |
| 877 | SessionInfo result = null; |
| 878 | boolean ended = false; |
| 879 | try |
| 880 | { |
| 881 | for ( int i=0; (i<metas.size()) && (result==null); i++ ) |
| 882 | { |
| 883 | LockMetaData meta = (LockMetaData) metas.get(i); |
| 884 | long startTime = System.currentTimeMillis(); |
| 885 | result = lock(index,threadId,txSerial,meta,info,wait,ensureCurrent,readOnly); |
| 886 | if ( wait > 0 ) |
| 887 | { |
| 888 | long endTime = System.currentTimeMillis(); |
| 889 | wait -= (endTime-startTime); |
| 890 | if ( wait <= 0 ) // Would mean infinite |
| 891 | wait = -1; // Expired instead |
| 892 | } |
| 893 | if ( result == null ) |
| 894 | lockedMetas.add(meta); |
| 895 | } |
| 896 | ended = true; |
| 897 | } finally { |
| 898 | if ( (!ended) || (result!=null) ) |
| 899 | { |
| 900 | // Some error happened, or a lock could not be established, |
| 901 | // so unlock all successfully locked ones, because either |
| 902 | // all locks are established, or none of them when the method |
| 903 | // returns. |
| 904 | for ( int o=0; o<lockedMetas.size(); o++ ) |
| 905 | unlock(index, threadId, txSerial, (LockMetaData) lockedMetas.get(o) ); |
| 906 | } |
| 907 | } |
| 908 | return result; |
| 909 | } |
| 910 | |
| 911 | /** |
| 912 | * Unlock given ids. |
| 913 | */ |
| 914 | public synchronized void unlock(int index, long threadId, long txSerial, List metas) |
| 915 | { |
| 916 | // Make it a server call |
| 917 | if ( nodeManager.getRole() == NodeManager.NodeRole.CLIENT ) |
| 918 | { |
| 919 | nodeManager.callServer(LockTracker.class.getName(), |
| 920 | "unlock",new Class[] { int.class, long.class, long.class, List.class }, |
| 921 | new Object[] { index, threadId, txSerial, metas }); |
| 922 | return; |
| 923 | } |
| 924 | // Go through all ids, and unlock'em all |
| 925 | for ( int i=0; i<metas.size(); i++ ) |
| 926 | unlock(index,threadId,txSerial,(LockMetaData) metas.get(i)); |
| 927 | // Notify waiting threads, that locks became unlocked. |
| 928 | notifyAll(); |
| 929 | } |
| 930 | |
| 931 | |
| 932 | public class LockEntry |
| 933 | { |
| 934 | public Long id; |
| 935 | public String name; |
| 936 | public Class objectClass; |
| 937 | |
| 938 | public long threadId; |
| 939 | public long txSerial; |
| 940 | public int index; |
| 941 | |
| 942 | public SessionInfo info; |
| 943 | public long lastModificationTime; |
| 944 | public int lockDepth; |
| 945 | public boolean readOnly; |
| 946 | } |
| 947 | |
| 948 | } |
| 949 | |
| 950 | |