Package com.google.common.util.concurrent

Class ForwardingFuture<V extends @Nullable Object>

java.lang.Object

com.google.common.collect.ForwardingObject

com.google.common.util.concurrent.ForwardingFuture<V>

All Implemented Interfaces:

Future<V>

Direct Known Subclasses:

ForwardingFuture.SimpleForwardingFuture, ForwardingListenableFuture

@GwtCompatible
public abstract class ForwardingFuture<V extends @Nullable Object>
extends ForwardingObject
implements Future<V>

A Future which forwards all its method calls to another future. Subclasses should override one or more methods to modify the behavior of the backing future as desired per the decorator pattern.

Most subclasses can just use ForwardingFuture.SimpleForwardingFuture.

Since:

1.0

Author:

Sven Mawson

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ForwardingFuture.SimpleForwardingFuture<V extends @Nullable Object>	A simplified version of ForwardingFuture where subclasses can pass in an already constructed Future as the delegate.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ForwardingFuture()	Constructor for use by subclasses.

Method Summary

Modifier and Type	Method	Description
boolean	cancel(boolean mayInterruptIfRunning)
protected abstract Future<? extends V>	delegate()	Returns the backing delegate instance that methods are forwarded to.
V	get()
V	get(long timeout, TimeUnit unit)
boolean	isCancelled()
boolean	isDone()

Methods inherited from class com.google.common.collect.ForwardingObject

toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ForwardingFuture

protected ForwardingFuture()

Constructor for use by subclasses.

Method Detail

delegate

protected abstract Future<? extends V> delegate()

Description copied from class: ForwardingObject

Returns the backing delegate instance that methods are forwarded to. Abstract subclasses generally override this method with an abstract method that has a more specific return type, such as ForwardingSet.delegate(). Concrete subclasses override this method to supply the instance being decorated.

Specified by:

delegate in class ForwardingObject

cancel

@CanIgnoreReturnValue
public boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface Future<V extends @Nullable Object>

isCancelled

public boolean isCancelled()

Specified by:

isCancelled in interface Future<V extends @Nullable Object>

isDone

public boolean isDone()

Specified by:

isDone in interface Future<V extends @Nullable Object>

get

@CanIgnoreReturnValue
public V get()
      throws InterruptedException,
             ExecutionException

Specified by:

get in interface Future<V extends @Nullable Object>

Throws:

InterruptedException

ExecutionException

get

@CanIgnoreReturnValue
public V get(long timeout,
             TimeUnit unit)
      throws InterruptedException,
             ExecutionException,
             TimeoutException

Specified by:

get in interface Future<V extends @Nullable Object>

Throws:

InterruptedException

ExecutionException

TimeoutException