net.schmizz.concurrent
Class Event<T extends Throwable>

java.lang.Object
  net.schmizz.concurrent.Event<T>

public class Event<T extends Throwable>
extends Object

An event can be set, cleared, or awaited, similar to Python's threading.event. The key difference is that a waiter may be delivered an exception of parameterized type T.

Uses Promise under the hood.

Constructor Summary

Event(String name, ExceptionChainer<T> chainer)
Creates this event with given name and exception chainer.

Event(String name, ExceptionChainer<T> chainer, ReentrantLock lock)
Creates this event with given name, exception chainer, and associated lock.

Method Summary

void	await() Await this event to have a definite true or false value.
void	await(long timeout, TimeUnit unit) Await this event to have a definite true or false value, for timeout duration.
void	clear() Clear this event.
void	deliverError(Throwable t) Deliver the error t (after chaining) to any present or future waiters.
boolean	hasWaiters()
boolean	inError()
boolean	isSet()
void	lock() Acquire the lock associated with this event.
void	set() Sets this event to be true.
String	toString()
boolean	tryAwait(long timeout, TimeUnit unit) Await this event to have a definite true or false value, for timeout duration.
void	unlock() Release the lock associated with this event.

Methods inherited from class java.lang.Object

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

Constructor Detail

Event

public Event(String name,
             ExceptionChainer<T> chainer)

Creates this event with given name and exception chainer. Allocates a new Lock object for this event.

Parameters:

name - name of this event

chainer - ExceptionChainer that will be used for chaining exceptions

Event

public Event(String name,
             ExceptionChainer<T> chainer,
             ReentrantLock lock)

Creates this event with given name, exception chainer, and associated lock.

Parameters:

name - name of this event

chainer - ExceptionChainer that will be used for chaining exceptions

lock - lock to use

Method Detail

set

public void set()

Sets this event to be true. Short for set(true).

clear

public void clear()

Clear this event. A cleared event !isSet().

deliverError

public void deliverError(Throwable t)

Deliver the error t (after chaining) to any present or future waiters.

isSet

public boolean isSet()

Returns:

whether this event is in a 'set' state. An event is set by a call to set() or deliverError

await

public void await()
           throws T extends Throwable

Await this event to have a definite true or false value.

Throws:

T - if another thread meanwhile informs this event of an error

T extends Throwable

await

public void await(long timeout,
                  TimeUnit unit)
           throws T extends Throwable

Await this event to have a definite true or false value, for timeout duration.

Parameters:

timeout - timeout

unit - the time unit for the timeout

Throws:

T - if another thread meanwhile informs this event of an error, or timeout expires

T extends Throwable

tryAwait

public boolean tryAwait(long timeout,
                        TimeUnit unit)
                 throws T extends Throwable

Await this event to have a definite true or false value, for timeout duration.

If the definite value is not available when the timeout expires, returns false.

Parameters:

timeout - timeout

unit - the time unit for the timeout

Throws:

T - if another thread meanwhile informs this event of an error

T extends Throwable

hasWaiters

public boolean hasWaiters()

Returns:

whether there are any threads waiting on this event to be set.

inError

public boolean inError()

Returns:

whether this event is in an error state i.e. has been delivered an error.

lock

public void lock()

Acquire the lock associated with this event.

unlock

public void unlock()

Release the lock associated with this event.

toString

public String toString()

Overrides:

toString in class Object