1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file and, per its terms, should not be removed:
30 *
31 * Copyright (c) 2000 World Wide Web Consortium,
32 * (Massachusetts Institute of Technology, Institut National de
33 * Recherche en Informatique et en Automatique, Keio University). All
34 * Rights Reserved. This program is distributed under the W3C's Software
35 * Intellectual Property License. This program is distributed in the
36 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
37 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
38 * PURPOSE.
39 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
40 */
41
42 package org.w3c.dom.events;
43
44 /**
45 * The <code>EventTarget</code> interface is implemented by all
46 * <code>Nodes</code> in an implementation which supports the DOM Event
47 * Model. Therefore, this interface can be obtained by using
48 * binding-specific casting methods on an instance of the <code>Node</code>
49 * interface. The interface allows registration and removal of
50 * <code>EventListeners</code> on an <code>EventTarget</code> and dispatch
51 * of events to that <code>EventTarget</code>.
52 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113'>Document Object Model (DOM) Level 2 Events Specification</a>.
53 * @since 1.5, DOM Level 2
54 */
55 public interface EventTarget {
56 /**
57 * This method allows the registration of event listeners on the event
58 * target. If an <code>EventListener</code> is added to an
59 * <code>EventTarget</code> while it is processing an event, it will not
60 * be triggered by the current actions but may be triggered during a
61 * later stage of event flow, such as the bubbling phase.
62 * <br> If multiple identical <code>EventListener</code>s are registered
63 * on the same <code>EventTarget</code> with the same parameters the
64 * duplicate instances are discarded. They do not cause the
65 * <code>EventListener</code> to be called twice and since they are
66 * discarded they do not need to be removed with the
67 * <code>removeEventListener</code> method.
68 * @param type The event type for which the user is registering
69 * @param listener The <code>listener</code> parameter takes an interface
70 * implemented by the user which contains the methods to be called
71 * when the event occurs.
72 * @param useCapture If true, <code>useCapture</code> indicates that the
73 * user wishes to initiate capture. After initiating capture, all
74 * events of the specified type will be dispatched to the registered
75 * <code>EventListener</code> before being dispatched to any
76 * <code>EventTargets</code> beneath them in the tree. Events which
77 * are bubbling upward through the tree will not trigger an
78 * <code>EventListener</code> designated to use capture.
79 */
80 public void addEventListener(String type,
81 EventListener listener,
82 boolean useCapture);
83
84 /**
85 * This method allows the removal of event listeners from the event
86 * target. If an <code>EventListener</code> is removed from an
87 * <code>EventTarget</code> while it is processing an event, it will not
88 * be triggered by the current actions. <code>EventListener</code>s can
89 * never be invoked after being removed.
90 * <br>Calling <code>removeEventListener</code> with arguments which do
91 * not identify any currently registered <code>EventListener</code> on
92 * the <code>EventTarget</code> has no effect.
93 * @param type Specifies the event type of the <code>EventListener</code>
94 * being removed.
95 * @param listener The <code>EventListener</code> parameter indicates the
96 * <code>EventListener </code> to be removed.
97 * @param useCapture Specifies whether the <code>EventListener</code>
98 * being removed was registered as a capturing listener or not. If a
99 * listener was registered twice, one with capture and one without,
100 * each must be removed separately. Removal of a capturing listener
101 * does not affect a non-capturing version of the same listener, and
102 * vice versa.
103 */
104 public void removeEventListener(String type,
105 EventListener listener,
106 boolean useCapture);
107
108 /**
109 * This method allows the dispatch of events into the implementations
110 * event model. Events dispatched in this manner will have the same
111 * capturing and bubbling behavior as events dispatched directly by the
112 * implementation. The target of the event is the
113 * <code> EventTarget</code> on which <code>dispatchEvent</code> is
114 * called.
115 * @param evt Specifies the event type, behavior, and contextual
116 * information to be used in processing the event.
117 * @return The return value of <code>dispatchEvent</code> indicates
118 * whether any of the listeners which handled the event called
119 * <code>preventDefault</code>. If <code>preventDefault</code> was
120 * called the value is false, else the value is true.
121 * @exception EventException
122 * UNSPECIFIED_EVENT_TYPE_ERR: Raised if the <code>Event</code>'s type
123 * was not specified by initializing the event before
124 * <code>dispatchEvent</code> was called. Specification of the
125 * <code>Event</code>'s type as <code>null</code> or an empty string
126 * will also trigger this exception.
127 */
128 public boolean dispatchEvent(Event evt)
129 throws EventException;
130
131 }