public abstract class

AbstractExecutorService

extends Object
implements ExecutorService
java.lang.Object
   ↳ java.util.concurrent.AbstractExecutorService
Known Direct Subclasses
Known Indirect Subclasses

Class Overview

Provides default implementations of ExecutorService execution methods. This class implements the submit, invokeAny and invokeAll methods using the default FutureTask class provided in this package. For example, the implementation of submit(Runnable) creates an associated FutureTask that is executed and returned. Subclasses overriding these methods to use different Future implementations should do so consistently for each of these methods.

Summary

Public Constructors
AbstractExecutorService()
Public Methods
<T> List<Future<T>> invokeAll(Collection<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.
<T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks)
Executes the given tasks, returning a list of Futures holding their status and results when all complete.
<T> T invokeAny(Collection<Callable<T>> tasks, long timeout, TimeUnit unit)
Executes the given tasks, returning the result of one that has completed successfully (i.e., without throwing an exception), if any do before the given timeout elapses.
<T> T invokeAny(Collection<Callable<T>> tasks)
Executes the given tasks, returning the result of one that has completed successfully (i.e., without throwing an exception), if any do.
Future<?> submit(Runnable task)
Submits a Runnable task for execution and returns a Future representing that task.
<T> Future<T> submit(Callable<T> task)
Submits a value-returning task for execution and returns a Future representing the pending results of the task.
<T> Future<T> submit(Runnable task, T result)
Submits a Runnable task for execution and returns a Future representing that task.
[Expand]
Inherited Methods
From class java.lang.Object
From interface java.util.concurrent.Executor
From interface java.util.concurrent.ExecutorService

Public Constructors

public AbstractExecutorService ()

Since: API Level 1

Public Methods

public List<Future<T>> invokeAll (Collection<Callable<T>> tasks, long timeout, TimeUnit unit)

Since: API Level 1

Executes the given tasks, returning a list of Futures holding their status and results when all complete or the timeout expires, whichever happens first. 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.

Parameters
tasks the collection of tasks
timeout the maximum time to wait
unit the time unit of the timeout argument
Returns
  • a list of Futures 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
InterruptedException

public List<Future<T>> invokeAll (Collection<Callable<T>> tasks)

Since: API Level 1

Executes the given tasks, returning a list of Futures holding their status and results when all complete. 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.

Parameters
tasks the collection of tasks
Returns
  • A list of Futures representing the tasks, in the same sequential order as produced by the iterator for the given task list, each of which has completed.
Throws
InterruptedException

public T invokeAny (Collection<Callable<T>> tasks, long timeout, TimeUnit unit)

Since: API Level 1

Executes the given tasks, returning the result of one that has completed successfully (i.e., without throwing an exception), if any do before the given timeout elapses. Upon normal or exceptional return, tasks that have not completed are cancelled. The results of this method are undefined if the given collection is modified while this operation is in progress.

Parameters
tasks the collection of tasks
timeout the maximum time to wait
unit the time unit of the timeout argument
Returns
  • the result returned by one of the tasks.
Throws
InterruptedException
ExecutionException
TimeoutException

public T invokeAny (Collection<Callable<T>> tasks)

Since: API Level 1

Executes the given tasks, returning the result of one that has completed successfully (i.e., without throwing an exception), if any do. Upon normal or exceptional return, tasks that have not completed are cancelled. The results of this method are undefined if the given collection is modified while this operation is in progress.

Parameters
tasks the collection of tasks
Returns
  • the result returned by one of the tasks
Throws
InterruptedException
ExecutionException

public Future<?> submit (Runnable task)

Since: API Level 1

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

Parameters
task the task to submit
Returns
  • a Future representing pending completion of the task
Throws
RejectedExecutionException
NullPointerException

public Future<T> submit (Callable<T> task)

Since: API Level 1

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.

Parameters
task the task to submit
Returns
  • a Future representing pending completion of the task
Throws
RejectedExecutionException
NullPointerException

public Future<T> submit (Runnable task, T result)

Since: API Level 1

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.

Parameters
task the task to submit
result the result to return
Returns
  • a Future representing pending completion of the task
Throws
RejectedExecutionException
NullPointerException