Top Description Fields Constructors Methods
com.google.common.util.concurrent

pack-priv abstract Class WrappingExecutorService

extends Object
implements ExecutorService
Class Inheritance
All Implemented Interfaces
java.util.concurrent.ExecutorService, java.lang.AutoCloseable, java.util.concurrent.Executor
Known Direct Subclasses
com.google.common.util.concurrent.WrappingScheduledExecutorService
Annotations
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
Static Imports
com.google.common.base.Preconditions.checkNotNull, .Throwables.throwIfUnchecked, com.google.common.util.concurrent.Platform.restoreInterruptIfIsInterruptedException
An abstract ExecutorService that allows subclasses to wrap tasks before they are submitted to the underlying executor.

Note that task wrapping may occur even if the task is never executed.

For delegation without task-wrapping, see ForwardingExecutorService.

Author
Chris Nokleberg

Field Summary

Modifier and TypeField and Description
private final ExecutorService
delegate

Constructor Summary

AccessConstructor and Description
protected
WrappingExecutorService(ExecutorService delegate)

Method Summary

Modifier and TypeMethod and Description
public final boolean
awaitTermination(long
the maximum time to wait
timeout, TimeUnit
the time unit of the timeout argument
unit)

Implements java.util.concurrent.ExecutorService.awaitTermination.

Blocks until all tasks have completed execution after a shutdown request, or the timeout occurs, or the current thread is interrupted, whichever happens first.
public final void
execute(Runnable
the runnable task
command)

Implements java.util.concurrent.Executor.execute.

Executes the given command at some time in the future.
public final <T extends @Nullable Object> List<Future<T>>
invokeAll(Collection<? extends Callable<T>>
the collection of tasks
tasks)

Implements java.util.concurrent.ExecutorService.invokeAll.

Executes the given tasks, returning a list of Futures holding their status and results when all complete.
public final <T extends @Nullable Object> List<Future<T>>
invokeAll(Collection<? extends Callable<T>>
the collection of tasks
tasks, long
the maximum time to wait
timeout, TimeUnit
the time unit of the timeout argument
unit)

Implements java.util.concurrent.ExecutorService.invokeAll.

Executes the given tasks, returning a list of Futures holding their status and results when all complete or the timeout expires, whichever happens first.
public final <T extends @Nullable Object> T
invokeAny(Collection<? extends Callable<T>>
the collection of tasks
tasks)

Implements java.util.concurrent.ExecutorService.invokeAny.

Executes the given tasks, returning the result of one that has completed successfully (i.e., without throwing an exception), if any do.
public final <T extends @Nullable Object> T
invokeAny(Collection<? extends Callable<T>>
the collection of tasks
tasks, long
the maximum time to wait
timeout, TimeUnit
the time unit of the timeout argument
unit)

Implements java.util.concurrent.ExecutorService.invokeAny.

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.
public final boolean
isShutdown()

Implements java.util.concurrent.ExecutorService.isShutdown.

Returns true if this executor has been shut down.
public final boolean
isTerminated()

Implements java.util.concurrent.ExecutorService.isTerminated.

Returns true if all tasks have completed following shut down.
public final void
shutdown()

Implements java.util.concurrent.ExecutorService.shutdown.

Initiates an orderly shutdown in which previously submitted tasks are executed, but no new tasks will be accepted.
public final List<Runnable>
shutdownNow()

Implements java.util.concurrent.ExecutorService.shutdownNow.

Attempts to stop all actively executing tasks, halts the processing of waiting tasks, and returns a list of the tasks that were awaiting execution.
public final <T extends @Nullable Object> Future<T>
submit(Callable<T>
the task to submit
task)

Implements java.util.concurrent.ExecutorService.submit.

Submits a value-returning task for execution and returns a Future representing the pending results of the task.
public final Future<?>
submit(Runnable
the task to submit
task)

Implements java.util.concurrent.ExecutorService.submit.

Submits a Runnable task for execution and returns a Future representing that task.
public final <T extends @Nullable Object> Future<T>
submit(Runnable
the task to submit
task, T
the result to return
result)

Implements java.util.concurrent.ExecutorService.submit.

Submits a Runnable task for execution and returns a Future representing that task.
protected abstract <T extends @Nullable Object> Callable<T>
wrapTask(Callable<T> callable)

Wraps a Callable for submission to the underlying executor.

protected Runnable
wrapTask(Runnable command)

Wraps a Runnable for submission to the underlying executor.

private <T extends @Nullable Object> ImmutableList<Callable<T>>
wrapTasks(Collection<? extends Callable<T>> tasks)

Wraps a collection of tasks.

Inherited from java.lang.Object:
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Field Detail

delegateback to summary
private final ExecutorService delegate

Constructor Detail

WrappingExecutorServiceback to summary
protected WrappingExecutorService(ExecutorService delegate)

Method Detail

awaitTerminationback to summary
public final boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException

Implements java.util.concurrent.ExecutorService.awaitTermination.

Doc from java.util.concurrent.ExecutorService.awaitTermination.

Blocks until all tasks have completed execution after a shutdown request, or the timeout occurs, or the current thread is interrupted, whichever happens first.

Parameters
timeout:long

the maximum time to wait

unit:TimeUnit

the time unit of the timeout argument

Returns:boolean

true if this executor terminated and false if the timeout elapsed before termination

Annotations
@Override
Exceptions
InterruptedException:
if interrupted while waiting
executeback to summary
public final void execute(Runnable command)

Implements java.util.concurrent.Executor.execute.

Doc from java.util.concurrent.Executor.execute.

Executes the given command at some time in the future. The command may execute in a new thread, in a pooled thread, or in the calling thread, at the discretion of the Executor implementation.

Parameters
command:Runnable

the runnable task

Annotations
@Override
invokeAllback to summary
public final <T extends @Nullable Object> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks) throws InterruptedException

Implements java.util.concurrent.ExecutorService.invokeAll.

Doc from java.util.concurrent.ExecutorService.invokeAll.

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.

Parameters
<T>
the type of the values returned from the tasks
tasks:Collection<? extends Callable<T>>

the collection of tasks

Returns:List<Future<T>>

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

Annotations
@Override
Exceptions
InterruptedException:
if interrupted while waiting, in which case unfinished tasks are cancelled
invokeAllback to summary
public final <T extends @Nullable Object> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) throws InterruptedException

Implements java.util.concurrent.ExecutorService.invokeAll.

Doc from java.util.concurrent.ExecutorService.invokeAll.

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.

Parameters
<T>
the type of the values returned from the tasks
tasks:Collection<? extends Callable<T>>

the collection of tasks

timeout:long

the maximum time to wait

unit:TimeUnit

the time unit of the timeout argument

Returns:List<Future<T>>

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.

Annotations
@Override
Exceptions
InterruptedException:
if interrupted while waiting, in which case unfinished tasks are cancelled
invokeAnyback to summary
public final <T extends @Nullable Object> T invokeAny(Collection<? extends Callable<T>> tasks) throws InterruptedException, ExecutionException

Implements java.util.concurrent.ExecutorService.invokeAny.

Doc from java.util.concurrent.ExecutorService.invokeAny.

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
<T>
the type of the values returned from the tasks
tasks:Collection<? extends Callable<T>>

the collection of tasks

Returns:T

the result returned by one of the tasks

Annotations
@Override
Exceptions
InterruptedException:
if interrupted while waiting
ExecutionException:
if no task successfully completes
invokeAnyback to summary
public final <T extends @Nullable Object> T invokeAny(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException

Implements java.util.concurrent.ExecutorService.invokeAny.

Doc from java.util.concurrent.ExecutorService.invokeAny.

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
<T>
the type of the values returned from the tasks
tasks:Collection<? extends Callable<T>>

the collection of tasks

timeout:long

the maximum time to wait

unit:TimeUnit

the time unit of the timeout argument

Returns:T

the result returned by one of the tasks

Annotations
@Override
Exceptions
InterruptedException:
if interrupted while waiting
ExecutionException:
if no task successfully completes
TimeoutException:
if the given timeout elapses before any task successfully completes
isShutdownback to summary
public final boolean isShutdown()

Implements java.util.concurrent.ExecutorService.isShutdown.

Doc from java.util.concurrent.ExecutorService.isShutdown.

Returns true if this executor has been shut down.

Returns:boolean

true if this executor has been shut down

Annotations
@Override
isTerminatedback to summary
public final boolean isTerminated()

Implements java.util.concurrent.ExecutorService.isTerminated.

Doc from java.util.concurrent.ExecutorService.isTerminated.

Returns true if all tasks have completed following shut down. Note that isTerminated is never true unless either shutdown or shutdownNow was called first.

Returns:boolean

true if all tasks have completed following shut down

Annotations
@Override
shutdownback to summary
public final void shutdown()

Implements java.util.concurrent.ExecutorService.shutdown.

Doc from java.util.concurrent.ExecutorService.shutdown.

Initiates an orderly shutdown in which previously submitted tasks are executed, but no new tasks will be accepted. Invocation has no additional effect if already shut down.

This method does not wait for previously submitted tasks to complete execution. Use awaitTermination to do that.

Annotations
@Override
shutdownNowback to summary
public final List<Runnable> shutdownNow()

Implements java.util.concurrent.ExecutorService.shutdownNow.

Doc from java.util.concurrent.ExecutorService.shutdownNow.

Attempts to stop all actively executing tasks, halts the processing of waiting tasks, and returns a list of the tasks that were awaiting execution.

This method does not wait for actively executing tasks to terminate. Use awaitTermination to do that.

There are no guarantees beyond best-effort attempts to stop processing actively executing tasks. For example, typical implementations will cancel via Thread#interrupt, so any task that fails to respond to interrupts may never terminate.

Returns:List<Runnable>

list of tasks that never commenced execution

Annotations
@Override
@CanIgnoreReturnValue
submitback to summary
public final <T extends @Nullable Object> Future<T> submit(Callable<T> task)

Implements java.util.concurrent.ExecutorService.submit.

Doc from java.util.concurrent.ExecutorService.submit.

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, java.security.PrivilegedAction to Callable form so they can be submitted.

Parameters
<T>
the type of the task's result
task:Callable<T>

the task to submit

Returns:Future<T>

a Future representing pending completion of the task

Annotations
@Override
submitback to summary
public final Future<?> submit(Runnable task)

Implements java.util.concurrent.ExecutorService.submit.

Doc from java.util.concurrent.ExecutorService.submit.

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:Runnable

the task to submit

Returns:Future<?>

a Future representing pending completion of the task

Annotations
@Override
submitback to summary
public final <T extends @Nullable Object> Future<T> submit(Runnable task, T result)

Implements java.util.concurrent.ExecutorService.submit.

Doc from java.util.concurrent.ExecutorService.submit.

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
<T>
the type of the result
task:Runnable

the task to submit

result:T

the result to return

Returns:Future<T>

a Future representing pending completion of the task

Annotations
@Override
wrapTaskback to summary
protected abstract <T extends @Nullable Object> Callable<T> wrapTask(Callable<T> callable)

Wraps a Callable for submission to the underlying executor. This method is also applied to any Runnable passed to the default implementation of wrapTask(Runnable).

wrapTaskback to summary
protected Runnable wrapTask(Runnable command)

Wraps a Runnable for submission to the underlying executor. The default implementation delegates to wrapTask(Callable).

wrapTasksback to summary
private <T extends @Nullable Object> ImmutableList<Callable<T>> wrapTasks(Collection<? extends Callable<T>> tasks)

Wraps a collection of tasks.

Exceptions
NullPointerException:
if any element of tasks is null