org.entityfs.lock.impl
Class EntityLockReentrantLockAdapterImpl

java.lang.Object
  org.entityfs.support.lang.ObjectProxySupport<ReentrantLock>
      org.entityfs.lock.impl.EntityLockReentrantLockAdapterImpl

All Implemented Interfaces:

Lock, EntityLock

public class EntityLockReentrantLockAdapterImpl
extends ObjectProxySupport<ReentrantLock>
implements EntityLock

This is an adapter to let a ReentrantLock implement the EntityLock interface. The adapter can be a read lock, a write lock or a lock that is both.

Since:

1.0

Author:

Karl Gustafsson

In_jar:

entityfs-core

Constructor Summary

EntityLockReentrantLockAdapterImpl(boolean fair, Lockable locked, boolean readLock, boolean writeLock)
Constructor.

Method Summary

int	getHoldCount() Get the hold count of the lock.
Lockable	getLocked() Get the locked object.
boolean	isDummy() Is this lock a dummy lock.
boolean	isHeldByCurrentThread() Is this lock held by the current thread? (This is implemented by ReentrantLock but not specified in the Lock interface.)
boolean	isReadLock() Returns true if this lock is a read lock.
boolean	isWriteLock() Returns true if this lock is a write lock.
void	lock()
void	lockInterruptibly()
Condition	newCondition()
boolean	tryLock()
boolean	tryLock(long timeout, TimeUnit unit)
void	unlock()

Methods inherited from class org.entityfs.support.lang.ObjectProxySupport

equals, getProxied, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

EntityLockReentrantLockAdapterImpl

public EntityLockReentrantLockAdapterImpl(boolean fair,
                                          Lockable locked,
                                          boolean readLock,
                                          boolean writeLock)

Constructor.

Parameters:

fair - Should fair queuing be used when acquiring locks?

locked - The locked object.

readLock - Is this a read lock for the entity?

writeLock - Is this a write lock for the entity?

Method Detail

getLocked

public Lockable getLocked()

Description copied from interface: EntityLock

Get the locked object. For locks that are not connected to any particular object (dummy locks, mostly), this method returns null.

Specified by:

getLocked in interface EntityLock

Returns:

The locked object or null if this lock is not connected to any particular object.

isReadLock

public boolean isReadLock()

Description copied from interface: EntityLock

Returns true if this lock is a read lock.

Specified by:

isReadLock in interface EntityLock

Returns:

true if this is a read lock, false if it is a write lock.

isWriteLock

public boolean isWriteLock()

Description copied from interface: EntityLock

Returns true if this lock is a write lock.

Specified by:

isWriteLock in interface EntityLock

Returns:

true if this is a write lock, false if this is a read lock.

lock

public void lock()

Specified by:

lock in interface Lock

newCondition

public Condition newCondition()

Specified by:

newCondition in interface Lock

unlock

public void unlock()

Specified by:

unlock in interface Lock

isHeldByCurrentThread

public boolean isHeldByCurrentThread()

Description copied from interface: EntityLock

Is this lock held by the current thread? (This is implemented by ReentrantLock but not specified in the Lock interface.)

Specified by:

isHeldByCurrentThread in interface EntityLock

Returns:

true if this lock is locked by the current thread.

tryLock

public boolean tryLock()

Specified by:

tryLock in interface Lock

tryLock

public boolean tryLock(long timeout,
                       TimeUnit unit)
                throws InterruptedException

Specified by:

tryLock in interface Lock

Throws:

InterruptedException

getHoldCount

public int getHoldCount()

Description copied from interface: EntityLock

Get the hold count of the lock. (How many Lock.lock() has been called minus the number of times Lock.unlock() has been called by the current thread.) If the hold count is 0, the lock is unlocked. The hold count can never be less than 0.

Specified by:

getHoldCount in interface EntityLock

Returns:

The hold count of the lock

lockInterruptibly

public void lockInterruptibly()
                       throws InterruptedException

Specified by:

lockInterruptibly in interface Lock

Throws:

InterruptedException

isDummy

public boolean isDummy()

Description copied from interface: EntityLock

Is this lock a dummy lock. A dummy lock does not actually do any locking.

Specified by:

isDummy in interface EntityLock

Returns:

false, always.