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1 /*
2  * @(#)ActiveEvent.java 1.13 03/12/19
3  *
4  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
5  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
6  */
7
8 package java.awt;
9
10 /**
11  * An interface for events that know how to dispatch themselves.
12  * By implementing this interface an event can be placed upon the event
13  * queue and its <code>dispatch()</code> method will be called when the event
14  * is dispatched, using the <code>EventDispatchThread</code>.
15  * <p>
16  * This is a very useful mechanism for avoiding deadlocks. If
17  * a thread is executing in a critical section (i.e., it has entered
18  * one or more monitors), calling other synchronized code may
19  * cause deadlocks. To avoid the potential deadlocks, an
20  * <code>ActiveEvent</code> can be created to run the second section of
21  * code at later time. If there is contention on the monitor,
22  * the second thread will simply block until the first thread
23  * has finished its work and exited its monitors.
24  * <p>
25  * For security reasons, it is often desirable to use an <code>ActiveEvent</code>
26  * to avoid calling untrusted code from a critical thread. For
27  * instance, peer implementations can use this facility to avoid
28  * making calls into user code from a system thread. Doing so avoids
29  * potential deadlocks and denial-of-service attacks.
30  *
31  * @author Timothy Prinzing
32  * @version 1.13 12/19/03
33  * @since 1.2
34  */
35 public interface ActiveEvent {
36
37     /**
38      * Dispatch the event to its target, listeners of the events source,
39      * or do whatever it is this event is supposed to do.
40      */
41     public void dispatch();
42 }
43
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