org.entityfs.lock.impl
Class AbstractLockAcquiringStrategy

java.lang.Object
  org.entityfs.lock.impl.AbstractLockAcquiringStrategy

All Implemented Interfaces:

LockAcquiringStrategy

Direct Known Subclasses:

SimpleLockAcquiringStrategy, TimeoutLockAcquiringStrategy

public abstract class AbstractLockAcquiringStrategy
extends Object
implements LockAcquiringStrategy

Abstract base class for lock acquiring strategy classes. Subclasses only have to implement the lockIt(Lock) method.

Since:

1.0

Author:

Karl Gustafsson

In_jar:

entityfs-core

Constructor Summary

AbstractLockAcquiringStrategy()

Method Summary

EntityLock	getEntityLock(Object identifier, EntityLockAdapter la, LogAdapter lga) Get a custom entity lock for an entity from its lock adapter.
Lock	getLock(Object identifier, LockAdapter la, LogAdapter lga) Lock a custom lock that is not tied to any specific entity.
EntityLock	getReadLock(EntityLockAdapter la, LogAdapter lga) Get a locked read lock for an entity from its lock adapter.
EntityLock	getWriteLock(EntityLockAdapter la, LogAdapter lga) Get a locked write lock for an entity from its lock adapter.
protected abstract boolean	lockIt(Lock l) Subclasses implement this to lock the given lock.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractLockAcquiringStrategy

public AbstractLockAcquiringStrategy()

Method Detail

lockIt

protected abstract boolean lockIt(Lock l)
                           throws InterruptedException

Subclasses implement this to lock the given lock.

Parameters:

l - The lock.

Returns:

true if successful, false otherwise. When false is returned, it is interpreted as due to a timeout.

Throws:

InterruptedException - If the thread is interrupted while trying to acquire the lock.

getReadLock

public final EntityLock getReadLock(EntityLockAdapter la,
                                    LogAdapter lga)

Description copied from interface: LockAcquiringStrategy

Get a locked read lock for an entity from its lock adapter.

Specified by:

getReadLock in interface LockAcquiringStrategy

Parameters:

la - The entity's lock adapter.

lga - The file system's current log adapter.

Returns:

A locked read lock.

getWriteLock

public EntityLock getWriteLock(EntityLockAdapter la,
                               LogAdapter lga)

Description copied from interface: LockAcquiringStrategy

Get a locked write lock for an entity from its lock adapter.

Specified by:

getWriteLock in interface LockAcquiringStrategy

Parameters:

la - The entity's lock adapter.

lga - The file system's current log adapter.

Returns:

A locked write lock.

getEntityLock

public EntityLock getEntityLock(Object identifier,
                                EntityLockAdapter la,
                                LogAdapter lga)

Description copied from interface: LockAcquiringStrategy

Get a custom entity lock for an entity from its lock adapter. The lock must have been registered with the entity lock adapter's createEntityLockForIdentifier(Object, boolean, boolean) method before it can be locked.

Specified by:

getEntityLock in interface LockAcquiringStrategy

Parameters:

identifier - The unique identifier for the lock.

la - The entity's lock adapter

lga - The file system's current log adapter.

Returns:

A locked custom lock.

getLock

public Lock getLock(Object identifier,
                    LockAdapter la,
                    LogAdapter lga)

Description copied from interface: LockAcquiringStrategy

Lock a custom lock that is not tied to any specific entity. The lock must have been registered with the lock adapter's createLockForIdentifier(Object) method before it can be locked.

Specified by:

getLock in interface LockAcquiringStrategy

Parameters:

identifier - The unique identifier for the lock.

la - The lock adapter.

lga - A log adapter

Returns:

A locked lock