org.xnio

Class AbstractIoFuture<T>

java.lang.Object

org.xnio.AbstractIoFuture<T>

Type Parameters:

T - the type of result that this operation produces

All Implemented Interfaces:

Cancellable, IoFuture<T>

Direct Known Subclasses:

FailedIoFuture

public abstract class AbstractIoFuture<T>
extends Object
implements IoFuture<T>

An abstract base class for IoFuture objects. Used to easily produce implementations.

Nested Class Summary

Nested classes/interfaces inherited from interface org.xnio.IoFuture

IoFuture.HandlingNotifier<T,A>, IoFuture.Notifier<T,A>, IoFuture.Status

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractIoFuture() Construct a new instance.

Method Summary

Modifier and Type	Method and Description
protected void	addCancelHandler(Cancellable cancellable) Add a cancellation handler.
<A> IoFuture<T>	addNotifier(IoFuture.Notifier<? super T,A> notifier, A attachment) Add a notifier to be called when this operation is complete.
IoFuture.Status	await() Wait for the operation to complete.
IoFuture.Status	await(long time, TimeUnit timeUnit) Wait for the operation to complete, with a timeout.
IoFuture.Status	awaitInterruptibly() Wait for the operation to complete.
IoFuture.Status	awaitInterruptibly(long time, TimeUnit timeUnit) Wait for the operation to complete, with a timeout.
IoFuture<T>	cancel() Cancel an operation.
T	get() Get the result of the operation.
IOException	getException() Get the failure reason.
T	getInterruptibly() Get the result of the operation.
protected Executor	getNotifierExecutor() Get the executor used to run asynchronous notifiers.
IoFuture.Status	getStatus() Get the current status.
protected void	runNotifier(Runnable runnable) Run a notifier.
protected boolean	setCancelled() Acknowledge the cancellation of this operation.
protected boolean	setException(IOException exception) Set the exception for this operation.
protected boolean	setResult(T result) Set the result for this operation.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractIoFuture

protected AbstractIoFuture()

Construct a new instance.

Method Detail

getStatus

public IoFuture.Status getStatus()

Get the current status.

Specified by:

getStatus in interface IoFuture<T>

Returns:

the current status

await

public IoFuture.Status await()

Wait for the operation to complete. This method will block until the status changes from IoFuture.Status.WAITING.

Specified by:

await in interface IoFuture<T>

Returns:

the new status

await

public IoFuture.Status await(long time,
                             TimeUnit timeUnit)

Wait for the operation to complete, with a timeout. This method will block until the status changes from IoFuture.Status.WAITING, or the given time elapses. If the time elapses before the operation is complete, IoFuture.Status.WAITING is returned.

Specified by:

await in interface IoFuture<T>

Parameters:

time - the amount of time to wait

timeUnit - the time unit

Returns:

the new status, or IoFuture.Status.WAITING if the timeout expired

awaitInterruptibly

public IoFuture.Status awaitInterruptibly()
                                   throws InterruptedException

Wait for the operation to complete. This method will block until the status changes from IoFuture.Status.WAITING, or the current thread is interrupted.

Specified by:

awaitInterruptibly in interface IoFuture<T>

Returns:

the new status

Throws:

InterruptedException - if the operation is interrupted

awaitInterruptibly

public IoFuture.Status awaitInterruptibly(long time,
                                          TimeUnit timeUnit)
                                   throws InterruptedException

Wait for the operation to complete, with a timeout. This method will block until the status changes from IoFuture.Status.WAITING, the given time elapses, or the current thread is interrupted. If the time elapses before the operation is complete, IoFuture.Status.WAITING is returned.

Specified by:

awaitInterruptibly in interface IoFuture<T>

Parameters:

time - the amount of time to wait

timeUnit - the time unit

Returns:

the new status, or IoFuture.Status.WAITING if the timeout expired

Throws:

InterruptedException - if the operation is interrupted

get

public T get()
      throws IOException,
             CancellationException

Get the result of the operation. If the operation is not complete, blocks until the operation completes. If the operation fails, or has already failed at the time this method is called, the failure reason is thrown.

Specified by:

get in interface IoFuture<T>

Returns:

the result of the operation

Throws:

IOException - if the operation failed

CancellationException - if the operation was cancelled

getInterruptibly

public T getInterruptibly()
                   throws IOException,
                          InterruptedException,
                          CancellationException

Get the result of the operation. If the operation is not complete, blocks until the operation completes. If the operation fails, or has already failed at the time this method is called, the failure reason is thrown. If the current thread is interrupted while waiting, an exception is thrown.

Specified by:

getInterruptibly in interface IoFuture<T>

Returns:

the result of the operation

Throws:

IOException - if the operation failed

InterruptedException - if the operation is interrupted

CancellationException - if the operation was cancelled

getException

public IOException getException()
                         throws IllegalStateException

Get the failure reason.

Specified by:

getException in interface IoFuture<T>

Returns:

the failure reason

Throws:

IllegalStateException - if the operation did not fail

addNotifier

public <A> IoFuture<T> addNotifier(IoFuture.Notifier<? super T,A> notifier,
                                   A attachment)

Add a notifier to be called when this operation is complete. If the operation is already complete, the notifier is called immediately, possibly in the caller's thread. The given attachment is provided to the notifier.

Specified by:

addNotifier in interface IoFuture<T>

Type Parameters:

A - the attachment type

Parameters:

notifier - the notifier to be called

attachment - the attachment to pass in to the notifier

Returns:

this instance

setException

protected boolean setException(IOException exception)

Set the exception for this operation. Any threads blocking on this instance will be unblocked.

Parameters:

exception - the exception to set

Returns:

false if the operation was already completed, true otherwise

setResult

protected boolean setResult(T result)

Set the result for this operation. Any threads blocking on this instance will be unblocked.

Parameters:

result - the result to set

Returns:

false if the operation was already completed, true otherwise

setCancelled

protected boolean setCancelled()

Acknowledge the cancellation of this operation.

Returns:

false if the operation was already completed, true otherwise

cancel

public IoFuture<T> cancel()

Cancel an operation. The actual cancel may be synchronous or asynchronous. Implementers will use this method to initiate the cancel; use the setCancelled() method to indicate that the cancel was successful. The default implementation calls any registered cancel handlers.

Specified by:

cancel in interface Cancellable

Specified by:

cancel in interface IoFuture<T>

Returns:

this IoFuture instance

addCancelHandler

protected void addCancelHandler(Cancellable cancellable)

Add a cancellation handler. The argument will be cancelled whenever this IoFuture is cancelled. If the IoFuture is already cancelled when this method is called, the handler will be called directly.

Parameters:

cancellable - the cancel handler

runNotifier

protected void runNotifier(Runnable runnable)

Run a notifier. Implementors will run the notifier, preferably in another thread. The default implementation runs the notifier using the Executor retrieved via getNotifierExecutor().

Parameters:

runnable - the runnable task

getNotifierExecutor

protected Executor getNotifierExecutor()

Get the executor used to run asynchronous notifiers. By default, this implementation simply returns the direct executor.

Returns:

the executor to use