org.infinispan.container
Interface EntryFactory

All Known Implementing Classes:

EntryFactoryImpl

public interface EntryFactory

A factory for constructing MVCCEntry instances for use in the InvocationContext. Implementations of this interface would typically wrap an internal CacheEntry with an MVCCEntry, optionally acquiring the necessary locks via the LockManager.

Since:

4.0

Author:

Manik Surtani (manik@jboss.org), Galder Zamarreño

Method Summary

boolean	acquireLock(InvocationContext ctx, Object key) Attempts to lock an entry if the lock isn't already held in the current scope, and records the lock in the context.
void	releaseLock(Object key)
CacheEntry	wrapEntryForReading(InvocationContext ctx, Object key) Wraps an entry for reading.
MVCCEntry	wrapEntryForWriting(InvocationContext ctx, InternalCacheEntry entry, boolean createIfAbsent, boolean forceLockIfAbsent, boolean alreadyLocked, boolean forRemoval, boolean undeleteIfNeeded) Wraps an entry for writing.
MVCCEntry	wrapEntryForWriting(InvocationContext ctx, Object key, boolean createIfAbsent, boolean forceLockIfAbsent, boolean alreadyLocked, boolean forRemoval, boolean undeleteIfNeeded) Wraps an entry for writing.

Method Detail

releaseLock

void releaseLock(Object key)

acquireLock

boolean acquireLock(InvocationContext ctx,
                    Object key)
                    throws InterruptedException,
                           TimeoutException

Attempts to lock an entry if the lock isn't already held in the current scope, and records the lock in the context.

Parameters:

ctx - context

key - Key to lock

Returns:

true if a lock was needed and acquired, false if it didn't need to acquire the lock (i.e., lock was already held)

Throws:

InterruptedException - if interrupted

TimeoutException - if we are unable to acquire the lock after a specified timeout.

wrapEntryForWriting

MVCCEntry wrapEntryForWriting(InvocationContext ctx,
                              Object key,
                              boolean createIfAbsent,
                              boolean forceLockIfAbsent,
                              boolean alreadyLocked,
                              boolean forRemoval,
                              boolean undeleteIfNeeded)
                              throws InterruptedException

Wraps an entry for writing. This would typically acquire write locks if necessary, and place the wrapped entry in the invocation context.

Parameters:

ctx - current invocation context

key - key to look up and wrap

createIfAbsent - if true, an entry is created if it does not exist in the data container.

forceLockIfAbsent - forces a lock even if the entry is absent

alreadyLocked - if true, this hint prevents the method from acquiring any locks and the existence and ownership of the lock is presumed.

forRemoval - if true, this hint informs this method that the lock is being acquired for removal.

undeleteIfNeeded - if true, if the entry is found in the current scope (perhaps a transaction) and is deleted, it will be undeleted. If false, it will be considered deleted.

Returns:

an MVCCEntry instance

Throws:

InterruptedException - when things go wrong, usually trying to acquire a lock

wrapEntryForWriting

MVCCEntry wrapEntryForWriting(InvocationContext ctx,
                              InternalCacheEntry entry,
                              boolean createIfAbsent,
                              boolean forceLockIfAbsent,
                              boolean alreadyLocked,
                              boolean forRemoval,
                              boolean undeleteIfNeeded)
                              throws InterruptedException

Wraps an entry for writing. This would typically acquire write locks if necessary, and place the wrapped entry in the invocation context.

Parameters:

ctx - current invocation context

entry - an internal entry to wrap

createIfAbsent - if true, an entry is created if it does not exist in the data container.

forceLockIfAbsent - forces a lock even if the entry is absent

alreadyLocked - if true, this hint prevents the method from acquiring any locks and the existence and ownership of the lock is presumed.

forRemoval - if true, this hint informs this method that the lock is being acquired for removal.

undeleteIfNeeded - if true, if the entry is found in the current scope (perhaps a transaction) and is deleted, it will be undeleted. If false, it will be considered deleted. * @return an MVCCEntry instance

Throws:

InterruptedException - when things go wrong, usually trying to acquire a lock

wrapEntryForReading

CacheEntry wrapEntryForReading(InvocationContext ctx,
                               Object key)
                               throws InterruptedException

Wraps an entry for reading. Usually this is just a raw CacheEntry but certain combinations of isolation levels and the presence of an ongoing JTA transaction may force this to be a proper, wrapped MVCCEntry. The entry is also typically placed in the invocation context.

Parameters:

ctx - current invocation context

key - key to look up and wrap

Returns:

an entry for reading

Throws:

InterruptedException - when things go wrong, usually trying to acquire a lock