1 /*
2  * Copyright (c) 2000 World Wide Web Consortium,
3  * (Massachusetts Institute of Technology, Institut National de
4  * Recherche en Informatique et en Automatique, Keio University). All
5  * Rights Reserved. This program is distributed under the W3C's Software
6  * Intellectual Property License. This program is distributed in the
7  * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
8  * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
9  * PURPOSE.
10  * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
11  */
12 
13 package org.w3c.dom.events;
14 
15 /**
16  * The <code>Event</code> interface is used to provide contextual information
17  * about an event to the handler processing the event. An object which
18  * implements the <code>Event</code> interface is generally passed as the
19  * first parameter to an event handler. More specific context information is
20  * passed to event handlers by deriving additional interfaces from
21  * <code>Event</code> which contain information directly relating to the
22  * type of event they accompany. These derived interfaces are also
23  * implemented by the object passed to the event listener.
24  * <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>.
25  * @since DOM Level 2
26  */
27 public interface Event {
28     // PhaseType
29     /**
30      * The current event phase is the capturing phase.
31      */
32     public static final short CAPTURING_PHASE           = 1;
33     /**
34      * The event is currently being evaluated at the target
35      * <code>EventTarget</code>.
36      */
37     public static final short AT_TARGET                 = 2;
38     /**
39      * The current event phase is the bubbling phase.
40      */
41     public static final short BUBBLING_PHASE            = 3;
42 
43     /**
44      * The name of the event (case-insensitive). The name must be an XML name.
45      */
getType()46     public String getType();
47 
48     /**
49      * Used to indicate the <code>EventTarget</code> to which the event was
50      * originally dispatched.
51      */
getTarget()52     public EventTarget getTarget();
53 
54     /**
55      * Used to indicate the <code>EventTarget</code> whose
56      * <code>EventListeners</code> are currently being processed. This is
57      * particularly useful during capturing and bubbling.
58      */
getCurrentTarget()59     public EventTarget getCurrentTarget();
60 
61     /**
62      * Used to indicate which phase of event flow is currently being
63      * evaluated.
64      */
getEventPhase()65     public short getEventPhase();
66 
67     /**
68      * Used to indicate whether or not an event is a bubbling event. If the
69      * event can bubble the value is true, else the value is false.
70      */
getBubbles()71     public boolean getBubbles();
72 
73     /**
74      * Used to indicate whether or not an event can have its default action
75      * prevented. If the default action can be prevented the value is true,
76      * else the value is false.
77      */
getCancelable()78     public boolean getCancelable();
79 
80     /**
81      *  Used to specify the time (in milliseconds relative to the epoch) at
82      * which the event was created. Due to the fact that some systems may
83      * not provide this information the value of <code>timeStamp</code> may
84      * be not available for all events. When not available, a value of 0
85      * will be returned. Examples of epoch time are the time of the system
86      * start or 0:0:0 UTC 1st January 1970.
87      */
getTimeStamp()88     public long getTimeStamp();
89 
90     /**
91      * The <code>stopPropagation</code> method is used prevent further
92      * propagation of an event during event flow. If this method is called
93      * by any <code>EventListener</code> the event will cease propagating
94      * through the tree. The event will complete dispatch to all listeners
95      * on the current <code>EventTarget</code> before event flow stops. This
96      * method may be used during any stage of event flow.
97      */
stopPropagation()98     public void stopPropagation();
99 
100     /**
101      * If an event is cancelable, the <code>preventDefault</code> method is
102      * used to signify that the event is to be canceled, meaning any default
103      * action normally taken by the implementation as a result of the event
104      * will not occur. If, during any stage of event flow, the
105      * <code>preventDefault</code> method is called the event is canceled.
106      * Any default action associated with the event will not occur. Calling
107      * this method for a non-cancelable event has no effect. Once
108      * <code>preventDefault</code> has been called it will remain in effect
109      * throughout the remainder of the event's propagation. This method may
110      * be used during any stage of event flow.
111      */
preventDefault()112     public void preventDefault();
113 
114     /**
115      * The <code>initEvent</code> method is used to initialize the value of an
116      * <code>Event</code> created through the <code>DocumentEvent</code>
117      * interface. This method may only be called before the
118      * <code>Event</code> has been dispatched via the
119      * <code>dispatchEvent</code> method, though it may be called multiple
120      * times during that phase if necessary. If called multiple times the
121      * final invocation takes precedence. If called from a subclass of
122      * <code>Event</code> interface only the values specified in the
123      * <code>initEvent</code> method are modified, all other attributes are
124      * left unchanged.
125      * @param eventTypeArg Specifies the event type. This type may be any
126      *   event type currently defined in this specification or a new event
127      *   type.. The string must be an XML name. Any new event type must not
128      *   begin with any upper, lower, or mixed case version of the string
129      *   "DOM". This prefix is reserved for future DOM event sets. It is
130      *   also strongly recommended that third parties adding their own
131      *   events use their own prefix to avoid confusion and lessen the
132      *   probability of conflicts with other new events.
133      * @param canBubbleArg Specifies whether or not the event can bubble.
134      * @param cancelableArg Specifies whether or not the event's default
135      *   action can be prevented.
136      */
initEvent(String eventTypeArg, boolean canBubbleArg, boolean cancelableArg)137     public void initEvent(String eventTypeArg,
138                           boolean canBubbleArg,
139                           boolean cancelableArg);
140 
141 }
142