org.exolab.core.foundation
Interface LockServiceIfc

public interface LockServiceIfc

Thew lock service is responsible for manmaging object level locking of PersistentObject instances.

Version:

$Revision: 1.1 $ $Date: 2000/02/22 07:37:55 $

Author:

Jim Alateras

Method Summary

void	acquireExclusiveLock(SessionIfc session, PersistentObject obj) Acquire an exclusive lock on the specified object.
void	acquireExclusiveLock(SessionIfc session, PersistentObject obj, long wait) Acquire an exclusive lock on the specified object.
void	acquireExclusiveLocks(SessionIfc session, java.util.Enumeration objs) Acquire exclusive locks on all the specified PersistentObject(s).
void	acquireExclusiveLocks(SessionIfc session, java.util.Enumeration objs, long wait) Acquire exclusive locks on the specified objects.
void	acquireReadLock(SessionIfc session, PersistentObject obj) Acquire a read lock on the specified PersistentObject.
void	acquireReadLock(SessionIfc session, PersistentObject obj, long wait) Acquire a read lock on the specified PersistentObject.
void	acquireReadLocks(SessionIfc session, java.util.Enumeration objs) Acquire read locks on all the specified PersistentObject(s).
void	acquireReadLocks(SessionIfc session, java.util.Enumeration objs, long wait) Acquire read locks on the specified PersistentObject(s).
boolean	aquireWriteLock(SessionIfc session, PersistentObject obj) Acquire a write lock on the specified PersistentObject.
boolean	aquireWriteLock(SessionIfc session, PersistentObject obj, long wait) Acquire a write lock on the specified PersistentObject.
boolean	aquireWriteLocks(SessionIfc session, java.util.Enumeration objs) Acquire write locks on all the specified PersistentObject(s).
boolean	aquireWriteLocks(SessionIfc session, java.util.Enumeration objs, long wait) Acquire write locks on the specified PersistentObject(s).
java.util.Enumeration	getAllLockedObjects() Return an enumeration of all locked object.
java.util.Enumeration	getLockedObjects(SessionIfc session) Return the set of objectslocked for the specified session
boolean	isLocked(PersistentObject obj) Check whether the specified object is locked
void	releaseAllLocks() Release all the locks maintained by the service.
void	releaseLock(PersistentObject obj) Release the lock on the specified object.
void	releaseLocks(java.util.Enumeration objs) Release all the locks specified by objs.
void	releaseLocks(SessionIfc session) Release all the locks associated with this session.

Method Detail

acquireReadLock

public void acquireReadLock(SessionIfc session,
                            PersistentObject obj)
                     throws FailedToAcquireLockException

Acquire a read lock on the specified PersistentObject. It will wait DefaultReadLockWaitTime ms, which is configurable. If the lock cannot be acquird wihin the specified time the function will throw FailedToAcquireLockException

Parameters:

obj - object to read-lock

Throws:

FailedToAcquireLockException

aquireWriteLock

public boolean aquireWriteLock(SessionIfc session,
                               PersistentObject obj)
                        throws FailedToAcquireLockException

Acquire a write lock on the specified PersistentObject. It will wait DefaultWriteLockWaitTime ms which is configurable. If the lock has not been acquired, within the specified time, the function will throw

Parameters:

obj - object to write-lock

Throws:

FailedToAcqwuireLockException

FailedToAcquireLockException

acquireExclusiveLock

public void acquireExclusiveLock(SessionIfc session,
                                 PersistentObject obj)
                          throws FailedToAcquireLockException

Acquire an exclusive lock on the specified object. It will wait for DefaultExclusiveLockWaitTime ms, whihc is configurable.An exclusive lock cannot be shared with other users, as read andwrite locks. If the lock cannot be acquired within the specified time then throw the FailedToAcquireLockException

Parameters:

obj - object to exclusively-lock

Throws:

FailedToAcquireLockException

acquireReadLock

public void acquireReadLock(SessionIfc session,
                            PersistentObject obj,
                            long wait)
                     throws FailedToAcquireLockException

Acquire a read lock on the specified PersistentObject. If the lock cannot be acquird wihin 'wait' ms the function will throw FailedToAcquireLockException

Parameters:

obj - object to read-lock

wait - time to wait in ms

Throws:

FailedToAcquireLockException

aquireWriteLock

public boolean aquireWriteLock(SessionIfc session,
                               PersistentObject obj,
                               long wait)
                        throws FailedToAcquireLockException

Acquire a write lock on the specified PersistentObject. If the lock cannot be acquired, within 'wait' ms the function will throw FailedToAcquireLockException

Parameters:

obj - object to write-lock

wait - time to wait in ms

Throws:

FailedToAcquireLockException

acquireExclusiveLock

public void acquireExclusiveLock(SessionIfc session,
                                 PersistentObject obj,
                                 long wait)
                          throws FailedToAcquireLockException

Acquire an exclusive lock on the specified object. An exclusive lock cannot be shared with other users, as read and write locks. If the lock cannot be acquired within 'wait' ms then throw the FailedToAcquireLockException

Parameters:

obj - object to exclusively-lock

wait - time to wait in ms

Throws:

FailedToAcquireLockException

acquireReadLocks

public void acquireReadLocks(SessionIfc session,
                             java.util.Enumeration objs)
                      throws FailedToAcquireLocksException

Acquire read locks on all the specified PersistentObject(s). It will wait DefaultReadLockWaitTime ms, which is configurable. If allthe locks cannot be acquird wihin the specified time the function will throw FailedToAcquireLocksException. This exception defines the list of locks that it failed to acquire

Throws:

FailedToAcquireLocksException

aquireWriteLocks

public boolean aquireWriteLocks(SessionIfc session,
                                java.util.Enumeration objs)
                         throws FailedToAcquireLocksException

Acquire write locks on all the specified PersistentObject(s). It will wait DefaultWriteLockWaitTime ms which is configurable. If all the lock cannot be acquired, within the specified time, the function will throw FailedToAcquireLocksException

Parameters:

objs - collection of PersistentObject instances

Throws:

FailedToAcquireLocksException

acquireExclusiveLocks

public void acquireExclusiveLocks(SessionIfc session,
                                  java.util.Enumeration objs)
                           throws FailedToAcquireLocksException

Acquire exclusive locks on all the specified PersistentObject(s). It will wait for DefaultExclusiveLockWaitTime ms, which is configurable. An exclusive lock cannot be shared with other users, as read and write locks. If all the locks cannot be acquired within the specified time then throw the FailedToAcquireLocksException

Parameters:

objs - collection of PersistentObject instances

Throws:

FailedToAcquireLockException

FailedToAcquireLocksException

acquireReadLocks

public void acquireReadLocks(SessionIfc session,
                             java.util.Enumeration objs,
                             long wait)
                      throws FailedToAcquireLocksException

Acquire read locks on the specified PersistentObject(s). If allthe lock cannot be acquird wihin 'wait' ms the function will throw FailedToAcquireLocksException

Parameters:

objs - collection of PersistentObject instances

wait - time to wait in ms

Throws:

FailedToAcquireLocksException

aquireWriteLocks

public boolean aquireWriteLocks(SessionIfc session,
                                java.util.Enumeration objs,
                                long wait)
                         throws FailedToAcquireLocksException

Acquire write locks on the specified PersistentObject(s). If all the lock cannot be acquired, within 'wait' ms the function will throw FailedToAcquireLocskException

Parameters:

objs - collection of PersistentObject instances

wait - time to wait in ms

Throws:

FailedToAcquireLocksException

acquireExclusiveLocks

public void acquireExclusiveLocks(SessionIfc session,
                                  java.util.Enumeration objs,
                                  long wait)
                           throws FailedToAcquireLocksException

Acquire exclusive locks on the specified objects. An exclusive lock cannot be shared with other users, as read and write locks. If all the lock cannot be acquired within 'wait' ms then throw the FailedToAcquireLocksException

Parameters:

objs - collection of PersistentObject instances

wait - time to wait in ms

Throws:

FailedToAcquireLocksException

releaseLock

public void releaseLock(PersistentObject obj)
                 throws FailedToReleaseLockException

Release the lock on the specified object. If the objects is not locked than throw FailedToReleaseLockException

Parameters:

obj - object to release

Throws:

FailedToReleaseLockException

releaseLocks

public void releaseLocks(java.util.Enumeration objs)
                  throws FailedToReleaseLocksException

Release all the locks specified by objs. If one or more of the locks are not available, or cannot be locked then throw the FailedToReleaseLocksException. This will contain a list of PersistentObj- ects that with no locks.

Parameters:

objs - objects to unlock

Throws:

FailedToReleaseLocksException

releaseLocks

public void releaseLocks(SessionIfc session)
                  throws FailedToReleaseLocksException

Release all the locks associated with this session. If it encounters a problem releasing one or more locks then throw FailedToReleaseLocksException.

Throws:

FailedToReleaseLocksException

isLocked

public boolean isLocked(PersistentObject obj)

Check whether the specified object is locked

Parameters:

obj - object to check

Returns:

boolean true if locked and false otherwise

getLockedObjects

public java.util.Enumeration getLockedObjects(SessionIfc session)

Return the set of objectslocked for the specified session

Parameters:

session - session to query

Returns:

Enumeration

getAllLockedObjects

public java.util.Enumeration getAllLockedObjects()

Return an enumeration of all locked object.

Returns:

Enumeration

releaseAllLocks

public void releaseAllLocks()

Release all the locks maintained by the service. If it encounters a problem releasing one or more locks then throw FailedToReleaseLocksException.

Throws:

FailedToReleaseLocksException