org.gridgain.grid.kernal

Class GridTaskFutureImpl<R>

java.lang.Object

java.util.concurrent.locks.AbstractOwnableSynchronizer

java.util.concurrent.locks.AbstractQueuedSynchronizer

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

org.gridgain.grid.kernal.GridTaskFutureImpl<R>

Type Parameters:

R - Type of the task result returning from GridComputeTask.reduce(List) method.

All Implemented Interfaces:

Externalizable, Serializable, GridComputeTaskFuture<R>, GridFuture<R>

public class GridTaskFutureImpl<R>
extends GridFutureAdapter<R>
implements GridComputeTaskFuture<R>

This class provide implementation for task future.

See Also:

Serialized Form

Nested Class Summary

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

AbstractQueuedSynchronizer.ConditionObject

Field Summary

Fields inherited from class org.gridgain.grid.util.future.GridFutureAdapter

log

Constructor Summary

Constructors

Constructor and Description
GridTaskFutureImpl() Required by Externalizable.
GridTaskFutureImpl(GridComputeTaskSession ses, GridKernalContext ctx)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	cancel() Default no-op implementation that always returns false.
boolean	cancelOnMasterLeave() Cancel task on master leave event.
GridComputeTaskSession	getTaskSession() Gets task timeout.
boolean	isMapped() Checks if "map" step has completed (which means that GridComputeTask.map(List, Object) method has finished).
boolean	onCancelled() Callback to notify that future is cancelled.
boolean	onDone(R res, Throwable err) Callback to notify that future is finished.
void	onMapped() Callback for completion of task mapping stage.
void	readExternal(ObjectInput in)
String	toString()
boolean	waitForMap() Waits until GridComputeTask.map(List, Object) method completes.
boolean	waitForMap(long timeout) Waits for a specified timeout in milliseconds for GridComputeTask.map(List, Object) method to complete.
boolean	waitForMap(long timeout, TimeUnit unit) Waits for a specified timeout in milliseconds for GridComputeTask.map(List, Object) method to complete.
void	writeExternal(ObjectOutput out)

Methods inherited from class org.gridgain.grid.util.future.GridFutureAdapter

chain, checkValid, concurrentNotify, concurrentNotify, duration, endTime, error, get, get, get, get0, isCancelled, isDone, isFailed, isValid, listenAsync, onDone, onDone, onDone, result, startTime, stopListenAsync, syncNotify, syncNotify, tryAcquireShared, tryReleaseShared

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

Methods inherited from interface org.gridgain.grid.compute.GridComputeTaskFuture

get, get, get

Methods inherited from interface org.gridgain.grid.GridFuture

chain, concurrentNotify, concurrentNotify, duration, isCancelled, isDone, listenAsync, startTime, stopListenAsync, syncNotify, syncNotify

Constructor Detail

GridTaskFutureImpl

public GridTaskFutureImpl()

Required by Externalizable.

GridTaskFutureImpl

public GridTaskFutureImpl(GridComputeTaskSession ses,
                  GridKernalContext ctx)

Parameters:

ses - Task session instance.

ctx - Kernal context.

Method Detail

getTaskSession

public GridComputeTaskSession getTaskSession()

Gets task timeout.

Specified by:

getTaskSession in interface GridComputeTaskFuture<R>

Returns:

Task timeout.

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 GridFutureAdapter.onCancelled() callback explicitly if cancellation indeed did happen.

Specified by:

cancel in interface GridFuture<R>

Overrides:

cancel in class GridFutureAdapter<R>

Returns:

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

Throws:

GridException - If cancellation failed.

cancelOnMasterLeave

public boolean cancelOnMasterLeave()
                            throws GridException

Cancel task on master leave event. Does not send cancel request to remote jobs and invokes master-leave callback on local jobs.

Returns:

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

Throws:

GridException - If failed.

isMapped

public boolean isMapped()

Checks if "map" step has completed (which means that GridComputeTask.map(List, Object) method has finished).

Specified by:

isMapped in interface GridComputeTaskFuture<R>

Returns:

true if map step has completed.

onMapped

public void onMapped()

Callback for completion of task mapping stage.

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.

Overrides:

onDone in class GridFutureAdapter<R>

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.

Overrides:

onCancelled in class GridFutureAdapter<R>

Returns:

True if cancel flag was set by this call.

waitForMap

public boolean waitForMap()
                   throws GridException

Waits until GridComputeTask.map(List, Object) method completes. This may be useful when it is desired to know the list of all job siblings for the task, as list of job siblings gets finalized only after the map step completes.

Note that this method will also return if the task fails.

Specified by:

waitForMap in interface GridComputeTaskFuture<R>

Returns:

true if map step has completed, false otherwise.

Throws:

GridException - If got interrupted while waiting or any other failure.

waitForMap

public boolean waitForMap(long timeout)
                   throws GridException

Waits for a specified timeout in milliseconds for GridComputeTask.map(List, Object) method to complete. This may be useful when it is desired to know the list of all job siblings for the task, as list of job siblings gets finalized only after the map step completes.

Specified by:

waitForMap in interface GridComputeTaskFuture<R>

Parameters:

timeout - Maximum time to wait.

Returns:

true if map step has completed, false otherwise.

Throws:

GridException - If got interrupted while waiting or any other failure.

waitForMap

public boolean waitForMap(long timeout,
                 TimeUnit unit)
                   throws GridException

Waits for a specified timeout in milliseconds for GridComputeTask.map(List, Object) method to complete. This may be useful when it is desired to know the list of all job siblings for the task, as list of job siblings gets finalized only after the map step completes.

Specified by:

waitForMap in interface GridComputeTaskFuture<R>

Parameters:

timeout - Maximum time to wait.

unit - Time unit for time parameter.

Returns:

true if map step has completed, false otherwise.

Throws:

GridException - If got interrupted while waiting or any other failure.

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Overrides:

writeExternal in class GridFutureAdapter<R>

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Overrides:

readExternal in class GridFutureAdapter<R>

Throws:

IOException

ClassNotFoundException

toString

public String toString()

Overrides:

toString in class GridFutureAdapter<R>