org.gridgain.grid
Interface GridTaskFuture<R>

Type Parameters:

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

All Superinterfaces:

Callable<R>, GridFuture<R>, GridMetadataAware, Serializable

public interface GridTaskFuture<R>
extends GridFuture<R>

This class defines a handler for asynchronous task execution. It's similar in design to standard JDK Future interface but has improved and easier to use exception hierarchy.

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Method Summary

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.
GridTaskSession	getTaskSession() Gets task session of execution grid task.
boolean	isMapped() Checks if "map" step has completed (which means that GridTask.map(List, Object) method has finished).
boolean	waitForMap() Waits until GridTask.map(List, Object) method completes.
boolean	waitForMap(long timeout) Waits for a specified timeout in milliseconds for GridTask.map(List, Object) method to complete.
boolean	waitForMap(long timeout, TimeUnit unit) Waits for a specified timeout in milliseconds for GridTask.map(List, Object) method to complete.

Methods inherited from interface org.gridgain.grid.GridFuture

cancel, concurrentNotify, concurrentNotify, duration, isCancelled, isDone, listenAsync, predicate, startTime, stopListenAsync, syncNotify, syncNotify

Methods inherited from interface org.gridgain.grid.GridMetadataAware

addMeta, addMetaIfAbsent, addMetaIfAbsent, allMeta, copyMeta, copyMeta, hasMeta, hasMeta, meta, putMetaIfAbsent, putMetaIfAbsent, removeMeta, removeMeta, replaceMeta

Methods inherited from interface java.util.concurrent.Callable

call

Method Detail

get

R get()
      throws GridException

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

Specified by:

get in interface GridFuture<R>

Throws:

GridTaskTimeoutException - If task execution timed out.

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

GridFutureCancelledException - Subclass of GridException throws if computation was cancelled.

GridException - If computation failed.

Returns:

Computation result.

get

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>

Throws:

GridTaskTimeoutException - If task execution timed out.

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.

Parameters:

timeout - The maximum time to wait in milliseconds.

Returns:

Computation result.

get

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>

Throws:

GridTaskTimeoutException - If task execution timed out.

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.

Parameters:

timeout - The maximum time to wait.

unit - The time unit of the timeout argument.

Returns:

Computation result.

getTaskSession

GridTaskSession getTaskSession()

Gets task session of execution grid task.

Returns:

Task session.

isMapped

boolean isMapped()

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

Returns:

true if map step has completed.

waitForMap

boolean waitForMap()
                   throws GridException

Waits until GridTask.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.

Throws:

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

Returns:

true if map step has completed, false otherwise.

waitForMap

boolean waitForMap(long timeout)
                   throws GridException

Waits for a specified timeout in milliseconds for GridTask.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.

Throws:

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

Parameters:

timeout - Maximum time to wait.

Returns:

true if map step has completed, false otherwise.

waitForMap

boolean waitForMap(long timeout,
                   TimeUnit unit)
                   throws GridException

Waits for a specified timeout in milliseconds for GridTask.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.

Throws:

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

Parameters:

timeout - Maximum time to wait.

unit - Time unit for time parameter.

Returns:

true if map step has completed, false otherwise.