ThreadPoolExecutor.CallerRunsPolicy

AI-generated Key Takeaways

• ThreadPoolExecutor.CallerRunsPolicy is a handler for rejected tasks that runs the rejected task directly in the calling thread.

• If the executor has been shut down, the task is discarded instead of being executed.

• It provides a simple way to handle task rejection by executing the task in the thread that submitted it.

• This policy can be useful for throttling the submission rate when the executor is overloaded.

public static class ThreadPoolExecutor.CallerRunsPolicy extends Object
implements RejectedExecutionHandler

A handler for rejected tasks that runs the rejected task directly in the calling thread of the execute method, unless the executor has been shut down, in which case the task is discarded.

Public Constructor Summary

CallerRunsPolicy() Creates a CallerRunsPolicy.

Public Method Summary

void	rejectedExecution(Runnable r, ThreadPoolExecutor e) Executes task r in the caller's thread, unless the executor has been shut down, in which case the task is discarded.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

From interface java.util.concurrent.RejectedExecutionHandler

abstract void

rejectedExecution(Runnable r, ThreadPoolExecutor executor) Method that may be invoked by a ThreadPoolExecutor when execute cannot accept a task.

Public Constructors

public CallerRunsPolicy ()

Creates a CallerRunsPolicy.

Public Methods

public void rejectedExecution (Runnable r, ThreadPoolExecutor e)

Executes task r in the caller's thread, unless the executor has been shut down, in which case the task is discarded.

Parameters

r	the runnable task requested to be executed
e	the executor attempting to execute this task