META-INF.modules.java.desktop.classes.java.awt.ActiveEvent Maven / Gradle / Ivy
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/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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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}.
*
* 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.
*
* 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();
}