Module com.conversantmedia.disruptor

Package com.conversantmedia.util.concurrent

Class SequenceLock

java.lang.Object

com.conversantmedia.util.concurrent.SequenceLock

All Implemented Interfaces:

OptimisticLock

public class SequenceLock
extends Object
implements OptimisticLock

http://www.hpl.hp.com/techreports/2012/HPL-2012-68.pdf Created by jcairns on 2/12/16.

Constructor Summary

Constructors

Constructor	Description
SequenceLock()

Method Summary

Modifier and Type	Method	Description
long	readLock()	Aquire a lock token for reading
boolean	readLockHeld(long lockToken)	check if optimistic locking succeeded
long	tryWriteLock()
long	tryWriteLock(long time, TimeUnit unit)
long	tryWriteLockInterruptibly()
void	unlock(long sequence)	"commit" or unlock the sequence when the write lock is held
long	writeLock()	Acquire the lock for writing, waiting if needed

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SequenceLock

public SequenceLock()

Method Detail

readLock

public long readLock()

Description copied from interface: OptimisticLock

Aquire a lock token for reading

Specified by:

readLock in interface OptimisticLock

Returns:

long - the token indicating the lock state

readLockHeld

public boolean readLockHeld(long lockToken)

Description copied from interface: OptimisticLock

check if optimistic locking succeeded

Specified by:

readLockHeld in interface OptimisticLock

Parameters:

lockToken - - the value returned from tryLock

Returns:

boolean - true if lock was held

writeLock

public long writeLock()

Description copied from interface: OptimisticLock

Acquire the lock for writing, waiting if needed

Specified by:

writeLock in interface OptimisticLock

Returns:

long - the token indicating the lock state

unlock

public void unlock(long sequence)

Description copied from interface: OptimisticLock

"commit" or unlock the sequence when the write lock is held

Specified by:

unlock in interface OptimisticLock

Parameters:

sequence - - lock sequence to unlock

tryWriteLock

public long tryWriteLock()

Specified by:

tryWriteLock in interface OptimisticLock

Returns:

long - the token indicating the lock state, or 0 if not available

tryWriteLock

public long tryWriteLock(long time,
                         TimeUnit unit)
                  throws InterruptedException

Specified by:

tryWriteLock in interface OptimisticLock

Parameters:

time - The time to wait to obtain the lock

unit - The units of time parameter

Returns:

long - the token indicating the lock state, or 0 if not available

Throws:

InterruptedException - on interrupt

tryWriteLockInterruptibly

public long tryWriteLockInterruptibly()
                               throws InterruptedException

Specified by:

tryWriteLockInterruptibly in interface OptimisticLock

Returns:

long - the token indicating the lock state

Throws:

InterruptedException - - on interrupt