javax.realtime

Interface ActiveEvent<T extends Releasable<T,D>,D extends ActiveEventDispatcher<D,T>>

All Superinterfaces:

Releasable<T,D>

All Known Implementing Classes:

RealtimeSignal, Signal

public interface ActiveEvent<T extends Releasable<T,D>,D extends ActiveEventDispatcher<D,T>>
extends Releasable<T,D>

This is the interface for defining the active event system. Classes implementing ActiveEvent are used to connect events that take place outside the Java virtual machine to RTSJ activities.

When an event takes place outside the Java virtual machine, some event-specific code within the Java virtual machine executes. That code notifies the ActiveEvent infrastructure of this event by calling a trigger method in the event.

An instance of this class holds a reference to its dispatcher. When isActive() is true, the dispatcher must also hold a reference to the instance. For this reason, whenever an active event instance is active, it is also a execution context, so that this reference can be safely held during this time. Only the active event instance must be assignable to its dispatcher instance under the memory assignment rules, but not visa versa.

Since:

RTSJ 2.0

Method Summary

Modifier and Type	Method and Description
void	disable() Changes the state of the event so that associated handlers are skipped on fire.
void	enable() Changes the state of the event so that associated handlers are released on fire.
boolean	isActive() Determines the activation state of this event, i.e., it has been started but not yet stopped again.
boolean	isRunning() Determines the running state of this event, i.e., it is both active and enabled.
void	start() Starts this active event.
void	start(boolean disabled) Starts this active event.
boolean	stop() Stops this active event.

Methods inherited from interface javax.realtime.Releasable

getDispatcher

Method Detail

isActive

boolean isActive()

Determines the activation state of this event, i.e., it has been started but not yet stopped again.

Returns:

true when active, false otherwise.

isRunning

boolean isRunning()

Determines the running state of this event, i.e., it is both active and enabled.

Returns:

true when active and enabled, false otherwise.

start

void start()
    throws StaticIllegalStateException

Starts this active event.

Throws:

StaticIllegalStateException - when this event has already been started.

start

void start(boolean disabled)
    throws StaticIllegalStateException

Starts this active event.

Throws:

StaticIllegalStateException - when this event has already been started.

Parameters:

disabled - True for starting in a disabled state.

stop

boolean stop()
      throws StaticIllegalStateException

Stops this active event.

Throws:

StaticIllegalStateException - when this event is not running.

Returns:

the previous enabled state.

enable

void enable()

Changes the state of the event so that associated handlers are released on fire. Each subclass provides a fire method as a means of dispatching its handlers when requested. This method enables that request mechanism.

disable

void disable()

Changes the state of the event so that associated handlers are skipped on fire. Each subclass provides a fire method as a means of dispatching its handlers when requested. This method disables that request mechanism.