ActiveEvent.java

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package java.awt;

/**
 * An interface for events that know how to dispatch themselves.
 * By implementing this interface an event can be placed upon the event
 * queue and its {@code dispatch()} method will be called when the event
 * is dispatched, using the {@code EventDispatchThread}.
 * <p>
 * This is a very useful mechanism for avoiding deadlocks. If
 * a thread is executing in a critical section (i.e., it has entered
 * one or more monitors), calling other synchronized code may
 * cause deadlocks. To avoid the potential deadlocks, an
 * {@code ActiveEvent} can be created to run the second section of
 * code at later time. If there is contention on the monitor,
 * the second thread will simply block until the first thread
 * has finished its work and exited its monitors.
 * <p>
 * For security reasons, it is often desirable to use an {@code ActiveEvent}
 * to avoid calling untrusted code from a critical thread. For
 * instance, peer implementations can use this facility to avoid
 * making calls into user code from a system thread. Doing so avoids
 * potential deadlocks and denial-of-service attacks.
 *
 * @author  Timothy Prinzing
 * @since   1.2
 */
public interface ActiveEvent {

    /**
     * Dispatch the event to its target, listeners of the events source,
     * or do whatever it is this event is supposed to do.
     */
    public void dispatch();
}