org.apache.hc.core5.concurrent

Class BasicFuture<T>

java.lang.Object

org.apache.hc.core5.concurrent.BasicFuture<T>

Type Parameters:

T - the future result type of an asynchronous operation.

All Implemented Interfaces:

Future<T>, Cancellable

Direct Known Subclasses:

ComplexFuture

public class BasicFuture<T>
extends Object
implements Future<T>, Cancellable

Basic implementation of the Future interface. BasicFuture can be put into a completed state by invoking any of the following methods: cancel(), failed(Exception), or completed(Object).

Since:

4.2

Constructor Summary

Constructors

Constructor and Description
BasicFuture(FutureCallback<T> callback)

Method Summary

Modifier and Type	Method and Description
boolean	cancel() Cancels the ongoing operation or process.
boolean	cancel(boolean mayInterruptIfRunning) Attempts to cancel execution of this task.
boolean	completed(T result)
boolean	failed(Exception exception)
T	get() Waits if necessary for the computation to complete, and then retrieves its result.
T	get(long timeout, TimeUnit unit) Waits if necessary for at most the given time for the computation to complete, and then retrieves its result, if available.
boolean	isCancelled() Returns true if this task was cancelled before it completed normally.
boolean	isDone() Returns true if this task completed.

Methods inherited from class java.lang.Object

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

Constructor Detail

BasicFuture

public BasicFuture(FutureCallback<T> callback)

Method Detail

cancel

public boolean cancel()

Description copied from interface: Cancellable

Cancels the ongoing operation or process.

Specified by:

cancel in interface Cancellable

Returns:

true if the operation or process has been cancelled as a result of this method call or false if it has already been cancelled or not started.

cancel

public boolean cancel(boolean mayInterruptIfRunning)

Description copied from interface: Future

Attempts to cancel execution of this task. This attempt will fail if the task has already completed, has already been cancelled, or could not be cancelled for some other reason. If successful, and this task has not started when cancel is called, this task should never run. If the task has already started, then the mayInterruptIfRunning parameter determines whether the thread executing this task should be interrupted in an attempt to stop the task.

After this method returns, subsequent calls to Future.isDone() will always return true. Subsequent calls to Future.isCancelled() will always return true if this method returned true.

Specified by:

cancel in interface Future<T>

Parameters:

mayInterruptIfRunning - true if the thread executing this task should be interrupted; otherwise, in-progress tasks are allowed to complete

Returns:

false if the task could not be cancelled, typically because it has already completed normally; true otherwise

completed

public boolean completed(T result)

failed

public boolean failed(Exception exception)

get

public T get()
      throws InterruptedException,
             ExecutionException

Description copied from interface: Future

Waits if necessary for the computation to complete, and then retrieves its result.

Specified by:

get in interface Future<T>

Returns:

the computed result

Throws:

InterruptedException - if the current thread was interrupted while waiting

ExecutionException - if the computation threw an exception

get

public T get(long timeout,
             TimeUnit unit)
      throws InterruptedException,
             ExecutionException,
             TimeoutException

Description copied from interface: Future

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

Specified by:

get in interface Future<T>

Parameters:

timeout - the maximum time to wait

unit - the time unit of the timeout argument

Returns:

the computed result

Throws:

InterruptedException - if the current thread was interrupted while waiting

ExecutionException - if the computation threw an exception

TimeoutException - if the wait timed out

isCancelled

public boolean isCancelled()

Description copied from interface: Future

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

Specified by:

isCancelled in interface Future<T>

Returns:

true if this task was cancelled before it completed

isDone

public boolean isDone()

Description copied from interface: Future

Returns true if this task completed. Completion may be due to normal termination, an exception, or cancellation -- in all of these cases, this method will return true.

Specified by:

isDone in interface Future<T>

Returns:

true if this task completed