Class Clutch.Pack

java.lang.Object

org.cojen.tupl.util.Latch

org.cojen.tupl.util.Clutch.Pack

Enclosing class:

Clutch

public static class Clutch.Pack
extends Latch

Sharable object for supporting contended clutches. Memory overhead (in bytes) is proportional to (number of slots) * (number of cores). The number of slots should be at least 16, to minimize cache line contention. As a convenience, this class also extends the Latch class, but the latching features aren't used here.

Nested Class Summary

Nested classes/interfaces inherited from class Latch

Latch.Condition

Modifier and Type	Class	Description
static class	Latch.Condition	Manages a queue of waiting threads, associated with a Latch instance.

Field Summary

Fields inherited from class Latch

EXCLUSIVE, SHARED, UNLATCHED

Modifier and Type	Field	Description
static final int	EXCLUSIVE
static final int	SHARED
static final int	UNLATCHED

Constructor Summary

Constructors

Constructor	Description
Pack(int numSlots)
Pack(int numSlots, int cores)

Method Summary

Methods inherited from class Latch

acquireExclusive, acquireExclusiveInterruptibly, acquireShared, acquireSharedInterruptibly, acquireSharedUncontended, acquireSharedUncontendedNanos, downgrade, hasQueuedThreads, release, releaseEither, releaseExclusive, releaseShared, toString, tryAcquireExclusive, tryAcquireExclusiveNanos, tryAcquireShared, tryAcquireSharedNanos, tryUpgrade, uponExclusive

Modifier and Type	Method	Description
void	acquireExclusive()	Acquire the exclusive latch, barging ahead of any waiting threads if possible.
void	acquireExclusiveInterruptibly()	Acquire the exclusive latch, aborting if interrupted.
void	acquireShared()	Acquire a shared latch, barging ahead of any waiting threads if possible.
void	acquireSharedInterruptibly()	Acquire a shared latch, aborting if interrupted.
boolean	acquireSharedUncontended()	Like tryAcquireShared, except blocks if an exclusive latch is held.
int	acquireSharedUncontendedNanos(long nanosTimeout)	Like tryAcquireSharedNanos, except blocks if an exclusive latch is held.
final void	downgrade()	Downgrade the held exclusive latch into a shared latch.
final boolean	hasQueuedThreads()
final void	release(boolean exclusive)	Convenience method, which releases the held exclusive or shared latch.
final void	releaseEither()	Releases an exclusive or shared latch.
final void	releaseExclusive()	Release the held exclusive latch.
void	releaseShared()	Release a held shared latch.
String	toString()
boolean	tryAcquireExclusive()	Try to acquire the exclusive latch, barging ahead of any waiting threads if possible.
boolean	tryAcquireExclusiveNanos(long nanosTimeout)	Attempt to acquire the exclusive latch, aborting if interrupted.
boolean	tryAcquireShared()	Try to acquire a shared latch, barging ahead of any waiting threads if possible.
boolean	tryAcquireSharedNanos(long nanosTimeout)	Attempt to acquire a shared latch, aborting if interrupted.
boolean	tryUpgrade()	Attempt to upgrade a held shared latch into an exclusive latch.
void	uponExclusive(Runnable cont)	Invokes the given continuation upon the latch being acquired exclusively.

Methods inherited from class Object

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

Constructor Details

Pack

public Pack(int numSlots)

Parameters:

numSlots - amount of contended clutches that this pack can support

Pack

public Pack(int numSlots,
 int cores)

Parameters:

numSlots - amount of contended clutches that this pack can support

cores - must be at least 1 CPU core