org.cache2k.impl.threading

Class Futures.WaitForAllFuture<V>

java.lang.Object

org.cache2k.impl.threading.Futures.WaitForAllFuture<V>

All Implemented Interfaces:

Future<V>

Enclosing class:

Futures

public static class Futures.WaitForAllFuture<V>
extends Object
implements Future<V>

A container for futures which waits for all futures to finish. Futures to wait for can be added with add(java.util.concurrent.Future) or the constructor. Waiting for all futures to finish is done via get().

The get method call will throw Exceptions from the added futures.

Constructor Summary

Constructors

Constructor and Description
Futures.WaitForAllFuture(Future<V>... _top)
Futures.WaitForAllFuture(Future<V> _top)

Method Summary

Methods

Modifier and Type	Method and Description
void	add(Future<V> f) Add a new future to the list for Futures we should wait for.
boolean	cancel(boolean mayInterruptIfRunning) Send cancel to all futures that are not yet cancelled.
V	get() Wait until everything is finished.
V	get(long timeout, TimeUnit unit)
boolean	isCancelled() Unsupported, it is not possible to implement useful semantics.
boolean	isDone() True, if every future is done or no future is contained.

Methods inherited from class java.lang.Object

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

Constructor Detail

Futures.WaitForAllFuture

public Futures.WaitForAllFuture(Future<V> _top)

Futures.WaitForAllFuture

@SafeVarargs
public Futures.WaitForAllFuture(Future<V>... _top)

Method Detail

add

public void add(Future<V> f)

Add a new future to the list for Futures we should wait for.

cancel

public boolean cancel(boolean mayInterruptIfRunning)

Send cancel to all futures that are not yet cancelled. Returns true if every future is in cancelled state.

Specified by:

cancel in interface Future<V>

isCancelled

public boolean isCancelled()

Unsupported, it is not possible to implement useful semantics.

Specified by:

isCancelled in interface Future<V>

isDone

public boolean isDone()

True, if every future is done or no future is contained.

The list of futures is not touched, since an exception may be thrown via get.

Specified by:

isDone in interface Future<V>

get

public V get()
      throws InterruptedException,
             ExecutionException

Wait until everything is finished. It may happen that a new future during this method waits for finishing another one. If this happens, we wait for that task also.

All get methods of the futures are executed to probe for possible exceptions. Futures completed without exceptions, will be removed for the list.

Implementation is a bit tricky. We need to call a potential stalling get outside the synchronized block, since new futures may come in in parallel.

Specified by:

get in interface Future<V>

Throws:

InterruptedException

ExecutionException

get

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

Specified by:

get in interface Future<V>

Throws:

InterruptedException

ExecutionException

TimeoutException