org.gridgain.grid

Interface GridFuture<R>

Type Parameters:

R - Type of the result for the future.

All Known Subinterfaces:

GridCacheAtomicFuture<K,R>, GridCacheFuture<R>, GridCacheMvccFuture<K,V,T>, GridCacheQueryFuture<T>, GridComputeTaskFuture<R>, GridDhtFuture<T>, GridDhtTopologyFuture, GridSchedulerFuture<R>

All Known Implementing Classes:

GridCacheDistributedFieldsQueryFuture, GridCacheDistributedQueryFuture, GridCacheFieldsQueryErrorFuture, GridCacheLocalFieldsQueryFuture, GridCacheLocalQueryFuture, GridCacheMultiTxFuture, GridCacheOptimisticCheckPreparedTxFuture, GridCachePessimisticCheckCommittedTxFuture, GridCacheQueryErrorFuture, GridCacheQueryFutureAdapter, GridCompoundFuture, GridCompoundIdentityFuture, GridDhtAssignmentFetchFuture, GridDhtAtomicUpdateFuture, GridDhtColocatedLockFuture, GridDhtColocatedTxFinishFuture, GridDhtColocatedTxPrepareFuture, GridDhtEmbeddedFuture, GridDhtFinishedFuture, GridDhtForceKeysFuture, GridDhtGetFuture, GridDhtLockFuture, GridDhtPartitionsExchangeFuture, GridDhtTxFinishFuture, GridDhtTxPrepareFuture, GridEmbeddedFuture, GridFinishedFuture, GridFinishedFutureEx, GridFutureAdapter, GridFutureAdapterEx, GridLocalLockFuture, GridNearAtomicUpdateFuture, GridNearGetFuture, GridNearLockFuture, GridNearTxFinishFuture, GridNearTxPrepareFuture, GridPartitionedGetFuture, GridStreamerStageExecutionFuture, GridTaskFutureImpl, GridWorkerFuture

public interface GridFuture<R>

Extension for standard Future interface. It adds simplified exception handling, functional programming support and ability to listen for future completion via functional callback.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	cancel() Cancels this future.
<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.
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.
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.
boolean	isCancelled() Returns true if this computation was cancelled before it completed normally.
boolean	isDone() Checks if computation is done.
void	listenAsync(GridInClosure<? super GridFuture<R>> lsnr) Registers listener closure to be asynchronously notified whenever future completes.
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.

Method Detail

get

R get()
      throws GridException

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

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

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).

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

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.

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.

cancel

boolean cancel()
               throws GridException

Cancels this future.

Returns:

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

Throws:

GridException - If cancellation failed.

isDone

boolean isDone()

Checks if computation is done.

Returns:

True if computation is done, false otherwise.

isCancelled

boolean isCancelled()

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

Returns:

True if this computation was cancelled before it completed normally.

startTime

long startTime()

Gets start time for this future.

Returns:

Start time for this future.

duration

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.

Returns:

Time in milliseconds this future has taken to execute.

syncNotify

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.

Parameters:

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

syncNotify

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.

Returns:

Synchronous listener notification flag.

concurrentNotify

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 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.

Parameters:

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

concurrentNotify

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 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.

Returns:

Concurrent listener notification flag

listenAsync

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

Registers listener closure to be asynchronously notified whenever future completes.

Parameters:

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

stopListenAsync

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.

Parameters:

lsnr - Listeners to remove.

chain

<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.

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.