org.axonframework.commandhandling.callbacks

Class FutureCallback<C,R>

java.lang.Object

java.util.concurrent.CompletableFuture<R>

org.axonframework.commandhandling.callbacks.FutureCallback<C,R>

Type Parameters:

R - the type of result of the command handling

C - The type of payload of the dispatched command

All Implemented Interfaces:

CompletionStage<R>, Future<R>, CommandCallback<C,R>

public class FutureCallback<C,R>
extends CompletableFuture<R>
implements CommandCallback<C,R>

Command Handler Callback that allows the dispatching thread to wait for the result of the callback, using the Future mechanism. This callback allows the caller to synchronize calls when an asynchronous command bus is being used.

Since:

0.6

Author:

Allard Buijze

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.CompletableFuture

CompletableFuture.AsynchronousCompletionTask

Constructor Summary

Constructors

Constructor and Description
FutureCallback()

Method Summary

Modifier and Type	Method and Description
boolean	awaitCompletion(long timeout, TimeUnit unit) Wait for completion of the command, or for the timeout to expire.
R	getResult() Waits if necessary for the command handling to complete, and then returns its result.
R	getResult(long timeout, TimeUnit unit) Waits if necessary for at most the given time for the command handling to complete, and then retrieves its result, if available.
void	onFailure(CommandMessage commandMessage, Throwable cause) Invoked when command handling execution resulted in an error.
void	onSuccess(CommandMessage<? extends C> commandMessage, R executionResult) Invoked when command handling execution was successful.

Methods inherited from class java.util.concurrent.CompletableFuture

acceptEither, acceptEitherAsync, acceptEitherAsync, allOf, anyOf, applyToEither, applyToEitherAsync, applyToEitherAsync, cancel, complete, completedFuture, completeExceptionally, exceptionally, get, get, getNow, getNumberOfDependents, handle, handleAsync, handleAsync, isCancelled, isCompletedExceptionally, isDone, join, obtrudeException, obtrudeValue, runAfterBoth, runAfterBothAsync, runAfterBothAsync, runAfterEither, runAfterEitherAsync, runAfterEitherAsync, runAsync, runAsync, supplyAsync, supplyAsync, thenAccept, thenAcceptAsync, thenAcceptAsync, thenAcceptBoth, thenAcceptBothAsync, thenAcceptBothAsync, thenApply, thenApplyAsync, thenApplyAsync, thenCombine, thenCombineAsync, thenCombineAsync, thenCompose, thenComposeAsync, thenComposeAsync, thenRun, thenRunAsync, thenRunAsync, toCompletableFuture, toString, whenComplete, whenCompleteAsync, whenCompleteAsync

Methods inherited from class java.lang.Object

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

Constructor Detail

FutureCallback

public FutureCallback()

Method Detail

onSuccess

public void onSuccess(CommandMessage<? extends C> commandMessage,
                      R executionResult)

Description copied from interface: CommandCallback

Invoked when command handling execution was successful.

Specified by:

onSuccess in interface CommandCallback<C,R>

Parameters:

commandMessage - The message that was dispatched

executionResult - The result of the command handling execution, if any.

onFailure

public void onFailure(CommandMessage commandMessage,
                      Throwable cause)

Description copied from interface: CommandCallback

Invoked when command handling execution resulted in an error.

Specified by:

onFailure in interface CommandCallback<C,R>

Parameters:

commandMessage - The message that was dispatched

cause - The exception raised during command handling

getResult

public R getResult()

Waits if necessary for the command handling to complete, and then returns its result.

Unlike CompletableFuture.get(long, java.util.concurrent.TimeUnit), this method will throw the original exception. Only checked exceptions are wrapped in a CommandExecutionException.

If the thread is interrupted while waiting, the interrupt flag is set back on the thread, and null is returned. To distinguish between an interrupt and a null result, use the CompletableFuture.isDone() method.

Returns:

the result of the command handler execution.

See Also:

CompletableFuture.get()

getResult

public R getResult(long timeout,
                   TimeUnit unit)

Waits if necessary for at most the given time for the command handling to complete, and then retrieves its result, if available.

Unlike CompletableFuture.get(long, java.util.concurrent.TimeUnit), this method will throw the original exception. Only checked exceptions are wrapped in a CommandExecutionException.

If the timeout expired or the thread is interrupted before completion, null is returned. In case of an interrupt, the interrupt flag will have been set back on the thread. To distinguish between an interrupt and a null result, use the CompletableFuture.isDone()

Parameters:

timeout - the maximum time to wait

unit - the time unit of the timeout argument

Returns:

the result of the command handler execution.

awaitCompletion

public boolean awaitCompletion(long timeout,
                               TimeUnit unit)

Wait for completion of the command, or for the timeout to expire.

Parameters:

timeout - The amount of time to wait for command processing to complete

unit - The unit in which the timeout is expressed

Returns:

true if command processing completed before the timeout expired, otherwise false.