Class Worker

java.lang.Object

org.cojen.tupl.util.Worker

public class Worker
extends Object

Simple task worker which has at most one background thread, and is expected to have only one thread enqueuing tasks. This class isn't thread safe for enqueuing tasks, and so the caller must provide its own mutual exclusion to protect against concurrent enqueues.

See Also:

• WorkerGroup

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Worker.Task	One-shot worker task instance.

Method Summary

Modifier and Type	Method	Description
void	enqueue(Worker.Task task)	Enqueue a task, blocking if necessary until space is available.
void	interrupt()	Interrupt the worker thread, if it exists.
void	join(boolean interrupt)	Waits until the worker queue is drained and possibly interrupt it.
static Worker	make(int maxSize, long keepAliveTime, TimeUnit unit, ThreadFactory threadFactory)
boolean	tryEnqueue(Worker.Task task)	Attempt to enqueue a task without blocking.

Methods inherited from class java.lang.Object

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

Method Details

make

public static Worker make(int maxSize,
 long keepAliveTime,
 TimeUnit unit,
 ThreadFactory threadFactory)

Parameters:

maxSize - maximum amount of tasks which can be enqueued

keepAliveTime - maximum idle time before worker thread exits

unit - keepAliveTime time unit

threadFactory - null for default

tryEnqueue

public boolean tryEnqueue(Worker.Task task)

Attempt to enqueue a task without blocking. When the task object is enqueued, it must not be used again for any other tasks.

Returns:

false if queue is full and task wasn't enqueued

enqueue

public void enqueue(Worker.Task task)

Enqueue a task, blocking if necessary until space is available. When the task object is enqueued, it must not be used again for any other tasks.

join

public void join(boolean interrupt)

Waits until the worker queue is drained and possibly interrupt it. If the worker thread is interrupted and exits, a new thread is started when new tasks are enqueued. The same mutual exclusion rules for enqueuing apply to this method too.

Parameters:

interrupt - pass true to interrupt the worker thread so that it exits

interrupt

public void interrupt()

Interrupt the worker thread, if it exists. If the worker thread is idle, this forces it to exit, but a new thread is started when new tasks are enqueued. This method can be safely called by any thread without any special mutual exclusion.