Package com.google.common.util.concurrent

Interface ListeningExecutorService

All Superinterfaces:

Executor, ExecutorService

All Known Subinterfaces:

ListeningScheduledExecutorService

All Known Implementing Classes:

AbstractListeningExecutorService, ForwardingListeningExecutorService

@DoNotMock("Use TestingExecutors.sameThreadScheduledExecutor, or wrap a real Executor from java.util.concurrent.Executors with MoreExecutors.listeningDecorator")
@GwtIncompatible
public interface ListeningExecutorService
extends ExecutorService

An ExecutorService that returns ListenableFuture instances. To create an instance from an existing ExecutorService, call MoreExecutors.listeningDecorator(ExecutorService).

Since:

10.0

Author:

Chris Povirk

Method Summary

Modifier and Type	Method	Description
<T extends @Nullable Object> List<Future<T>>	invokeAll(Collection<? extends Callable<T>> tasks)	Executes the given tasks, returning a list of Futures holding their status and results when all complete.
<T extends @Nullable Object> List<Future<T>>	invokeAll(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)	Executes the given tasks, returning a list of Futures holding their status and results when all complete or the timeout expires, whichever happens first.
ListenableFuture<?>	submit(Runnable task)	Submits a Runnable task for execution and returns a Future representing that task.
<T extends @Nullable Object> ListenableFuture<T>	submit(Runnable task, T result)	Submits a Runnable task for execution and returns a Future representing that task.
<T extends @Nullable Object> ListenableFuture<T>	submit(Callable<T> task)	Submits a value-returning task for execution and returns a Future representing the pending results of the task.

Methods inherited from interface java.util.concurrent.Executor

execute

Methods inherited from interface java.util.concurrent.ExecutorService

awaitTermination, invokeAny, invokeAny, isShutdown, isTerminated, shutdown, shutdownNow

Method Detail

submit

<T extends @Nullable Object> ListenableFuture<T> submit(Callable<T> task)

Description copied from interface: java.util.concurrent.ExecutorService

Submits a value-returning task for execution and returns a Future representing the pending results of the task. The Future's get method will return the task's result upon successful completion.

If you would like to immediately block waiting for a task, you can use constructions of the form result = exec.submit(aCallable).get();

Note: The Executors class includes a set of methods that can convert some other common closure-like objects, for example, PrivilegedAction to Callable form so they can be submitted.

Specified by:

submit in interface ExecutorService

Type Parameters:

T - the type of the task's result

Parameters:

task - the task to submit

Returns:

a ListenableFuture representing pending completion of the task

Throws:

RejectedExecutionException - if the task cannot be scheduled for execution

submit

ListenableFuture<?> submit(Runnable task)

Description copied from interface: java.util.concurrent.ExecutorService

Submits a Runnable task for execution and returns a Future representing that task. The Future's get method will return null upon successful completion.

Specified by:

submit in interface ExecutorService

Parameters:

task - the task to submit

Returns:

a ListenableFuture representing pending completion of the task

Throws:

RejectedExecutionException - if the task cannot be scheduled for execution

submit

<T extends @Nullable Object> ListenableFuture<T> submit(Runnable task,
                                                        T result)

Description copied from interface: java.util.concurrent.ExecutorService

Submits a Runnable task for execution and returns a Future representing that task. The Future's get method will return the given result upon successful completion.

Specified by:

submit in interface ExecutorService

Type Parameters:

T - the type of the result

Parameters:

task - the task to submit

result - the result to return

Returns:

a ListenableFuture representing pending completion of the task

Throws:

RejectedExecutionException - if the task cannot be scheduled for execution

invokeAll

<T extends @Nullable Object> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
                                                throws InterruptedException

Executes the given tasks, returning a list of Futures holding their status and results when all complete. Future.isDone() is true for each element of the returned list. Note that a completed task could have terminated either normally or by throwing an exception. The results of this method are undefined if the given collection is modified while this operation is in progress.

All elements in the returned list must be ListenableFuture instances. The easiest way to obtain a List<ListenableFuture<T>> from this method is an unchecked (but safe) cast:

   @SuppressWarnings("unchecked") // guaranteed by invokeAll contract
   List<ListenableFuture<T>> futures = (List) executor.invokeAll(tasks);
 

Specified by:

invokeAll in interface ExecutorService

Type Parameters:

T - the type of the values returned from the tasks

Parameters:

tasks - the collection of tasks

Returns:

A list of ListenableFuture instances representing the tasks, in the same sequential order as produced by the iterator for the given task list, each of which has completed.

Throws:

RejectedExecutionException - if any task cannot be scheduled for execution

NullPointerException - if any task is null

InterruptedException - if interrupted while waiting, in which case unfinished tasks are cancelled

invokeAll

<T extends @Nullable Object> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks,
                                                       long timeout,
                                                       TimeUnit unit)
                                                throws InterruptedException

Executes the given tasks, returning a list of Futures holding their status and results when all complete or the timeout expires, whichever happens first. Future.isDone() is true for each element of the returned list. Upon return, tasks that have not completed are cancelled. Note that a completed task could have terminated either normally or by throwing an exception. The results of this method are undefined if the given collection is modified while this operation is in progress.

All elements in the returned list must be ListenableFuture instances. The easiest way to obtain a List<ListenableFuture<T>> from this method is an unchecked (but safe) cast:

   @SuppressWarnings("unchecked") // guaranteed by invokeAll contract
   List<ListenableFuture<T>> futures = (List) executor.invokeAll(tasks, timeout, unit);
 

Specified by:

invokeAll in interface ExecutorService

Type Parameters:

T - the type of the values returned from the tasks

Parameters:

tasks - the collection of tasks

timeout - the maximum time to wait

unit - the time unit of the timeout argument

Returns:

a list of ListenableFuture instances representing the tasks, in the same sequential order as produced by the iterator for the given task list. If the operation did not time out, each task will have completed. If it did time out, some of these tasks will not have completed.

Throws:

RejectedExecutionException - if any task cannot be scheduled for execution

NullPointerException - if any task is null

InterruptedException - if interrupted while waiting, in which case unfinished tasks are cancelled