org.gridgain.grid.util.future

Class GridFutureAdapter<R>

java.lang.Object

java.util.concurrent.locks.AbstractOwnableSynchronizer

java.util.concurrent.locks.AbstractQueuedSynchronizer

org.gridgain.grid.util.future.GridFutureAdapter<R>

All Implemented Interfaces:

Externalizable, Serializable, GridFuture<R>

Direct Known Subclasses:

GridCacheMultiTxFuture, GridCacheQueryFutureAdapter, GridCompoundFuture, GridDhtAssignmentFetchFuture, GridDhtAtomicUpdateFuture, GridDhtPartitionsExchangeFuture, GridEmbeddedFuture, GridLocalLockFuture, GridNearAtomicUpdateFuture, GridStreamerStageExecutionFuture, GridTaskFutureImpl, GridWorkerFuture

public class GridFutureAdapter<R>
extends AbstractQueuedSynchronizer
implements GridFuture<R>, Externalizable

Future adapter.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.locks.AbstractQueuedSynchronizer

AbstractQueuedSynchronizer.ConditionObject

Field Summary

Fields

Modifier and Type	Field and Description
protected GridKernalContext	ctx Context.
protected static GridLogger	log Logger.

Constructor Summary

Constructors

Constructor and Description
GridFutureAdapter() Empty constructor required for Externalizable.
GridFutureAdapter(GridKernalContext ctx)
GridFutureAdapter(GridKernalContext ctx, boolean syncNotify)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	cancel() Default no-op implementation that always returns false.
<T> GridFuture<T>	chain(GridClosure<? super GridFuture<R>,T> doneCb) Make a chained future to convert result of this future (when complete) into a new format.
protected void	checkValid() Checks that future is in usable state.
boolean	concurrentNotify() Gets value concurrent listener notification flag.
void	concurrentNotify(boolean concurNotify) Flag to turn on or off concurrent listener notification.
long	duration() Gets duration in milliseconds between start of the future and current time if future is not finished, or between start and finish of this future.
long	endTime()
protected Throwable	error()
R	get() Synchronously waits for completion of the computation and returns computation result.
R	get(long timeout) Synchronously waits for completion of the computation for up to the timeout specified and returns computation result.
R	get(long timeout, TimeUnit unit) Synchronously waits for completion of the computation for up to the timeout specified and returns computation result.
protected R	get0(long nanosTimeout)
boolean	isCancelled() Returns true if this computation was cancelled before it completed normally.
boolean	isDone() Checks if computation is done.
boolean	isFailed()
protected boolean	isValid()
void	listenAsync(GridInClosure<? super GridFuture<R>> lsnr) Registers listener closure to be asynchronously notified whenever future completes.
boolean	onCancelled() Callback to notify that future is cancelled.
boolean	onDone() Callback to notify that future is finished with null result.
boolean	onDone(R res) Callback to notify that future is finished.
boolean	onDone(R res, Throwable err) Callback to notify that future is finished.
boolean	onDone(Throwable err) Callback to notify that future is finished.
void	readExternal(ObjectInput in)
protected R	result()
long	startTime() Gets start time for this future.
void	stopListenAsync(GridInClosure<? super GridFuture<R>>... lsnr) Removes given listeners from the future.
boolean	syncNotify() Gets value of synchronous listener notification flag.
void	syncNotify(boolean syncNotify) Flag to turn on or off synchronous listener notification.
String	toString()
protected int	tryAcquireShared(int ignore)
protected boolean	tryReleaseShared(int ignore)
void	writeExternal(ObjectOutput out)

Methods inherited from class java.util.concurrent.locks.AbstractQueuedSynchronizer

acquire, acquireInterruptibly, acquireShared, acquireSharedInterruptibly, compareAndSetState, getExclusiveQueuedThreads, getFirstQueuedThread, getQueuedThreads, getQueueLength, getSharedQueuedThreads, getState, getWaitingThreads, getWaitQueueLength, hasContended, hasQueuedPredecessors, hasQueuedThreads, hasWaiters, isHeldExclusively, isQueued, owns, release, releaseShared, setState, tryAcquire, tryAcquireNanos, tryAcquireSharedNanos, tryRelease

Methods inherited from class java.util.concurrent.locks.AbstractOwnableSynchronizer

getExclusiveOwnerThread, setExclusiveOwnerThread

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static GridLogger log

Logger.

ctx

protected GridKernalContext ctx

Context.

Constructor Detail

GridFutureAdapter

public GridFutureAdapter()

Empty constructor required for Externalizable.

GridFutureAdapter

public GridFutureAdapter(GridKernalContext ctx)

Parameters:

ctx - Kernal context.

GridFutureAdapter

public GridFutureAdapter(GridKernalContext ctx,
                 boolean syncNotify)

Parameters:

syncNotify - Synchronous notify flag.

ctx - Kernal context.

Method Detail

startTime

public long startTime()

Gets start time for this future.

Specified by:

startTime in interface GridFuture<R>

Returns:

Start time for this future.

duration

public long duration()

Gets duration in milliseconds between start of the future and current time if future is not finished, or between start and finish of this future.

Specified by:

duration in interface GridFuture<R>

Returns:

Time in milliseconds this future has taken to execute.

endTime

public long endTime()

Returns:

Future end time.

concurrentNotify

public boolean concurrentNotify()

Gets value concurrent listener notification flag. This flag comes into play only when a future has more than one listener subscribed to it. If this flag is true, then all listeners will be notified concurrently by different threads; otherwise, listeners will be notified one after another within one thread (depending on GridFuture.syncNotify() flag, these notifications may happen either in the same thread which started the future, or in a different thread).

Default value is false. To change the default, set GridSystemProperties.GG_FUT_CONCURRENT_NOTIFICATION system property to true.

Specified by:

concurrentNotify in interface GridFuture<R>

Returns:

Concurrent listener notification flag

concurrentNotify

public void concurrentNotify(boolean concurNotify)

Flag to turn on or off concurrent listener notification. This flag comes into play only when a future has more than one listener subscribed to it. If this flag is true, then all listeners will be notified concurrently by different threads; otherwise, listeners will be notified one after another within one thread (depending on GridFuture.syncNotify() flag, these notifications may happen either in the same thread which started the future, or in a different thread).

Default value is false. To change the default, set GridSystemProperties.GG_FUT_CONCURRENT_NOTIFICATION system property to true.

Specified by:

concurrentNotify in interface GridFuture<R>

Parameters:

concurNotify - Flag to turn on or off concurrent listener notification.

syncNotify

public boolean syncNotify()

Gets value of synchronous listener notification flag. If this flag is true, then upon future completion the notification may happen in the same thread that created the future. This becomes especially important when adding listener to a future that is already done - if this flag is true, then listener will be immediately notified within the same thread.

Default value is false. To change the default, set GridSystemProperties.GG_FUT_SYNC_NOTIFICATION system property to true.

Specified by:

syncNotify in interface GridFuture<R>

Returns:

Synchronous listener notification flag.

syncNotify

public void syncNotify(boolean syncNotify)

Flag to turn on or off synchronous listener notification. If this flag is true, then upon future completion the notification may happen in the same thread that created the future. This becomes especially important when adding listener to a future that is already done - if this flag is true, then listener will be immediately notified within the same thread.

Default value is false. To change the default, set GridSystemProperties.GG_FUT_SYNC_NOTIFICATION system property to true.

Specified by:

syncNotify in interface GridFuture<R>

Parameters:

syncNotify - Flag to turn on or off synchronous listener notification.

checkValid

protected void checkValid()

Checks that future is in usable state.

isValid

protected boolean isValid()

Returns:

Valid flag.

error

protected Throwable error()

Returns:

Value of error.

result

protected R result()

Returns:

Value of result.

get

public R get()
      throws GridException

Synchronously waits for completion of the computation and returns computation result.

Specified by:

get in interface GridFuture<R>

Returns:

Computation result.

Throws:

GridInterruptedException - Subclass of GridException thrown if the wait was interrupted.

GridFutureCancelledException - Subclass of GridException throws if computation was cancelled.

GridException - If computation failed.

get

public R get(long timeout)
      throws GridException

Synchronously waits for completion of the computation for up to the timeout specified and returns computation result. This method is equivalent to calling get(long, TimeUnit.MILLISECONDS).

Specified by:

get in interface GridFuture<R>

Parameters:

timeout - The maximum time to wait in milliseconds.

Returns:

Computation result.

Throws:

GridInterruptedException - Subclass of GridException thrown if the wait was interrupted.

GridFutureTimeoutException - Subclass of GridException thrown if the wait was timed out.

GridFutureCancelledException - Subclass of GridException throws if computation was cancelled.

GridException - If computation failed.

get

public R get(long timeout,
    TimeUnit unit)
      throws GridException

Synchronously waits for completion of the computation for up to the timeout specified and returns computation result.

Specified by:

get in interface GridFuture<R>

Parameters:

timeout - The maximum time to wait.

unit - The time unit of the timeout argument.

Returns:

Computation result.

Throws:

GridInterruptedException - Subclass of GridException thrown if the wait was interrupted.

GridFutureTimeoutException - Subclass of GridException thrown if the wait was timed out.

GridFutureCancelledException - Subclass of GridException throws if computation was cancelled.

GridException - If computation failed.

get0

@Nullable
protected R get0(long nanosTimeout)
          throws InterruptedException,
                 GridException

Parameters:

nanosTimeout - Timeout (nanoseconds).

Returns:

Result.

Throws:

InterruptedException - If interrupted.

GridFutureTimeoutException - If timeout reached before computation completed.

GridException - If error occurred.

listenAsync

public void listenAsync(@Nullable
               GridInClosure<? super GridFuture<R>> lsnr)

Registers listener closure to be asynchronously notified whenever future completes.

Specified by:

listenAsync in interface GridFuture<R>

Parameters:

lsnr - Listener closure to register. If not provided - this method is no-op.

stopListenAsync

public void stopListenAsync(@Nullable
                   GridInClosure<? super GridFuture<R>>... lsnr)

Removes given listeners from the future. If no listener is passed in, then all listeners will be removed.

Specified by:

stopListenAsync in interface GridFuture<R>

Parameters:

lsnr - Listeners to remove.

chain

public <T> GridFuture<T> chain(GridClosure<? super GridFuture<R>,T> doneCb)

Make a chained future to convert result of this future (when complete) into a new format. It is guaranteed that done callback will be called only ONCE.

Specified by:

chain in interface GridFuture<R>

Parameters:

doneCb - Done callback that is applied to this future when it finishes to produce chained future result.

Returns:

Chained future that finishes after this future completes and done callback is called.

cancel

public boolean cancel()
               throws GridException

Default no-op implementation that always returns false. Futures that do support cancellation should override this method and call onCancelled() callback explicitly if cancellation indeed did happen.

Specified by:

cancel in interface GridFuture<R>

Returns:

True if future was canceled (i.e. was not finished prior to this call).

Throws:

GridException - If cancellation failed.

isDone

public boolean isDone()

Checks if computation is done.

Specified by:

isDone in interface GridFuture<R>

Returns:

True if computation is done, false otherwise.

isFailed

public boolean isFailed()

Returns:

Checks is future is completed with exception.

isCancelled

public boolean isCancelled()

Returns true if this computation was cancelled before it completed normally.

Specified by:

isCancelled in interface GridFuture<R>

Returns:

True if this computation was cancelled before it completed normally.

onDone

public final boolean onDone()

Callback to notify that future is finished with null result. This method must delegate to onDone(Object, Throwable) method.

Returns:

True if result was set by this call.

onDone

public final boolean onDone(@Nullable
             R res)

Callback to notify that future is finished. This method must delegate to onDone(Object, Throwable) method.

Parameters:

res - Result.

Returns:

True if result was set by this call.

onDone

public final boolean onDone(@Nullable
             Throwable err)

Callback to notify that future is finished. This method must delegate to onDone(Object, Throwable) method.

Parameters:

err - Error.

Returns:

True if result was set by this call.

onDone

public boolean onDone(@Nullable
             R res,
             @Nullable
             Throwable err)

Callback to notify that future is finished. Note that if non-null exception is passed in the result value will be ignored.

Parameters:

res - Optional result.

err - Optional error.

Returns:

True if result was set by this call.

onCancelled

public boolean onCancelled()

Callback to notify that future is cancelled.

Returns:

True if cancel flag was set by this call.

tryAcquireShared

protected final int tryAcquireShared(int ignore)

Overrides:

tryAcquireShared in class AbstractQueuedSynchronizer

tryReleaseShared

protected final boolean tryReleaseShared(int ignore)

Overrides:

tryReleaseShared in class AbstractQueuedSynchronizer

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Throws:

IOException

ClassNotFoundException

toString

public String toString()

Overrides:

toString in class AbstractQueuedSynchronizer