org.infinispan.util.concurrent.locks.containers

Class AbstractPerEntryLockContainer<L extends Lock>

java.lang.Object

org.infinispan.util.concurrent.locks.containers.AbstractLockContainer<L>

org.infinispan.util.concurrent.locks.containers.AbstractPerEntryLockContainer<L>

All Implemented Interfaces:

LockContainer<L>

Direct Known Subclasses:

OwnableReentrantPerEntryLockContainer, ReentrantPerEntryLockContainer

public abstract class AbstractPerEntryLockContainer<L extends Lock>
extends AbstractLockContainer<L>

An abstract lock container that creates and maintains a new lock per entry

Since:

4.0

Author:

Manik Surtani

Field Summary

Fields

Modifier and Type	Field and Description
protected ConcurrentMap<Object,L>	locks

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractPerEntryLockContainer(int concurrencyLevel)

Method Summary

Methods

Modifier and Type	Method and Description
L	acquireLock(Object lockOwner, Object key, long timeout, TimeUnit unit) Attempts to acquire a lock for the given object within certain time boundaries defined by the timeout and time unit parameters.
L	getLock(Object key)
int	getLockId(Object key) Returns the 'id' of the lock that will be used to guard access to a given key in the cache.
int	getNumLocksHeld()
protected abstract L	newLock()
void	releaseLock(Object lockOwner, Object key) Release lock on the given key.
int	size()

Methods inherited from class org.infinispan.util.concurrent.locks.containers.AbstractLockContainer

safeRelease, tryLock, unlock

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.infinispan.util.concurrent.locks.containers.LockContainer

isLocked, ownsLock

Field Detail

locks

protected final ConcurrentMap<Object,L extends Lock> locks

Constructor Detail

AbstractPerEntryLockContainer

protected AbstractPerEntryLockContainer(int concurrencyLevel)

Method Detail

newLock

protected abstract L newLock()

getLock

public final L getLock(Object key)

Parameters:

key - object

Returns:

the lock for a specific object

getNumLocksHeld

public int getNumLocksHeld()

Returns:

number of locks held

size

public int size()

Returns:

the size of the shared lock pool

acquireLock

public L acquireLock(Object lockOwner,
            Object key,
            long timeout,
            TimeUnit unit)
                           throws InterruptedException

Description copied from interface: LockContainer

Attempts to acquire a lock for the given object within certain time boundaries defined by the timeout and time unit parameters.

key - Object to acquire lock on

timeout - Time after which the lock acquisition will fail

unit - Time unit of the given timeout

Returns:

If lock was acquired it returns the corresponding Lock object. If lock was not acquired, it returns null

Throws:

InterruptedException - If the lock acquisition was interrupted

releaseLock

public void releaseLock(Object lockOwner,
               Object key)

Description copied from interface: LockContainer

Release lock on the given key.

key - Object on which lock is to be removed

getLockId

public int getLockId(Object key)

Description copied from interface: LockContainer

Returns the 'id' of the lock that will be used to guard access to a given key in the cache. Particularly useful if Lock Striping is used and locks may guard more than one key. This mechanism can be used to check whether keys may end up sharing the same lock.

If lock-striping is not used, the identity hash code of the lock created for this specific key is returned. While this may not be of much value, it is done to maintain API compatibility of this method regardless of underlying locking scheme.

Parameters:

key - key to test for

Returns:

the ID of the lock.