Java LockMode.FORCE屬性代碼示例

/**
 * Convert from the Hibernate specific LockMode to the JPA defined LockModeType.
 *
 * @param lockMode The Hibernate LockMode.
 *
 * @return The JPA LockModeType
 */
public static LockModeType convertToLockModeType(LockMode lockMode) {
	if ( lockMode == LockMode.NONE ) {
		return LockModeType.NONE;
	}
	else if ( lockMode == LockMode.OPTIMISTIC || lockMode == LockMode.READ ) {
		return LockModeType.OPTIMISTIC;
	}
	else if ( lockMode == LockMode.OPTIMISTIC_FORCE_INCREMENT || lockMode == LockMode.WRITE ) {
		return LockModeType.OPTIMISTIC_FORCE_INCREMENT;
	}
	else if ( lockMode == LockMode.PESSIMISTIC_READ ) {
		return LockModeType.PESSIMISTIC_READ;
	}
	else if ( lockMode == LockMode.PESSIMISTIC_WRITE
			|| lockMode == LockMode.UPGRADE
			|| lockMode == LockMode.UPGRADE_NOWAIT
               || lockMode == LockMode.UPGRADE_SKIPLOCKED) {
		return LockModeType.PESSIMISTIC_WRITE;
	}
	else if ( lockMode == LockMode.PESSIMISTIC_FORCE_INCREMENT
			|| lockMode == LockMode.FORCE ) {
		return LockModeType.PESSIMISTIC_FORCE_INCREMENT;
	}
	throw new AssertionFailure( "unhandled lock mode " + lockMode );
}
 

private static LockMode getLockMode(String lockMode) {
	if ( lockMode == null || "read".equals( lockMode ) ) {
		return LockMode.READ;
	}
	else if ( "none".equals( lockMode ) ) {
		return LockMode.NONE;
	}
	else if ( "upgrade".equals( lockMode ) ) {
		return LockMode.UPGRADE;
	}
	else if ( "upgrade-nowait".equals( lockMode ) ) {
		return LockMode.UPGRADE_NOWAIT;
	}
	else if ( "upgrade-skiplocked".equals( lockMode )) {
		return LockMode.UPGRADE_SKIPLOCKED;
	}
	else if ( "write".equals( lockMode ) ) {
		return LockMode.WRITE;
	}
	else if ( "force".equals( lockMode ) ) {
		return LockMode.FORCE;
	}
	else if ( "optimistic".equals( lockMode ) ) {
		return LockMode.OPTIMISTIC;
	}
	else if ( "optimistic_force_increment".equals( lockMode ) ) {
		return LockMode.OPTIMISTIC_FORCE_INCREMENT;
	}
	else if ( "pessimistic_read".equals( lockMode ) ) {
		return LockMode.PESSIMISTIC_READ;
	}
	else if ( "pessimistic_write".equals( lockMode ) ) {
		return LockMode.PESSIMISTIC_WRITE;
	}
	else if ( "pessimistic_force_increment".equals( lockMode ) ) {
		return LockMode.PESSIMISTIC_FORCE_INCREMENT;
	}
	else {
		throw new MappingException( "unknown lockmode" );
	}
}
 

/**
 * Performs a pessimistic lock upgrade on a given entity, if needed.
 *
 * @param object The entity for which to upgrade the lock.
 * @param entry The entity's EntityEntry instance.
 * @param lockOptions contains the requested lock mode.
 * @param source The session which is the source of the event being processed.
 */
protected void upgradeLock(Object object, EntityEntry entry, LockOptions lockOptions, EventSource source) {

	LockMode requestedLockMode = lockOptions.getLockMode();
	if ( requestedLockMode.greaterThan( entry.getLockMode() ) ) {
		// The user requested a "greater" (i.e. more restrictive) form of
		// pessimistic lock

		if ( entry.getStatus() != Status.MANAGED ) {
			throw new ObjectDeletedException(
					"attempted to lock a deleted instance",
					entry.getId(),
					entry.getPersister().getEntityName()
			);
		}

		final EntityPersister persister = entry.getPersister();

		if ( log.isTraceEnabled() ) {
			log.tracev(
					"Locking {0} in mode: {1}",
					MessageHelper.infoString( persister, entry.getId(), source.getFactory() ),
					requestedLockMode
			);
		}

		final SoftLock lock;
		final CacheKey ck;
		if ( persister.hasCache() ) {
			ck = source.generateCacheKey( entry.getId(), persister.getIdentifierType(), persister.getRootEntityName() );
			lock = persister.getCacheAccessStrategy().lockItem( ck, entry.getVersion() );
		}
		else {
			ck = null;
			lock = null;
		}

		try {
			if ( persister.isVersioned() && requestedLockMode == LockMode.FORCE  ) {
				// todo : should we check the current isolation mode explicitly?
				Object nextVersion = persister.forceVersionIncrement(
						entry.getId(), entry.getVersion(), source
				);
				entry.forceLocked( object, nextVersion );
			}
			else {
				persister.lock( entry.getId(), entry.getVersion(), object, lockOptions, source );
			}
			entry.setLockMode(requestedLockMode);
		}
		finally {
			// the database now holds a lock + the object is flushed from the cache,
			// so release the soft lock
			if ( persister.hasCache() ) {
				persister.getCacheAccessStrategy().unlockItem( ck, lock );
			}
		}

	}
}