/*
* @(#)InputEvent.java 1.34 04/06/02
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.awt.event;
import java.awt.Event;
import java.awt.Component;
import java.awt.GraphicsEnvironment;
import java.awt.Toolkit;
/**
* The root event class for all component-level input events.
*
* Input events are delivered to listeners before they are
* processed normally by the source where they originated.
* This allows listeners and component subclasses to "consume"
* the event so that the source will not process them in their
* default manner. For example, consuming mousePressed events
* on a Button component will prevent the Button from being
* activated.
*
* @author Carl Quinn
* @version 1.34 06/02/04
*
* @see KeyEvent
* @see KeyAdapter
* @see MouseEvent
* @see MouseAdapter
* @see MouseMotionAdapter
*
* @since 1.1
*/
public abstract class InputEvent extends ComponentEvent {
/**
* The Shift key modifier constant.
* It is recommended that SHIFT_DOWN_MASK be used instead.
*/
public static final int SHIFT_MASK = Event.SHIFT_MASK;
/**
* The Control key modifier constant.
* It is recommended that CTRL_DOWN_MASK be used instead.
*/
public static final int CTRL_MASK = Event.CTRL_MASK;
/**
* The Meta key modifier constant.
* It is recommended that META_DOWN_MASK be used instead.
*/
public static final int META_MASK = Event.META_MASK;
/**
* The Alt key modifier constant.
* It is recommended that ALT_DOWN_MASK be used instead.
*/
public static final int ALT_MASK = Event.ALT_MASK;
/**
* The AltGraph key modifier constant.
*/
public static final int ALT_GRAPH_MASK = 1 << 5;
/**
* The Mouse Button1 modifier constant.
* It is recommended that BUTTON1_DOWN_MASK be used instead.
*/
public static final int BUTTON1_MASK = 1 << 4;
/**
* The Mouse Button2 modifier constant.
* It is recommended that BUTTON2_DOWN_MASK be used instead.
* Note that BUTTON2_MASK has the same value as ALT_MASK.
*/
public static final int BUTTON2_MASK = Event.ALT_MASK;
/**
* The Mouse Button3 modifier constant.
* It is recommended that BUTTON3_DOWN_MASK be used instead.
* Note that BUTTON3_MASK has the same value as META_MASK.
*/
public static final int BUTTON3_MASK = Event.META_MASK;
/**
* The Shift key extended modifier constant.
* @since 1.4
*/
public static final int SHIFT_DOWN_MASK = 1 << 6;
/**
* The Control key extended modifier constant.
* @since 1.4
*/
public static final int CTRL_DOWN_MASK = 1 << 7;
/**
* The Meta key extended modifier constant.
* @since 1.4
*/
public static final int META_DOWN_MASK = 1 << 8;
/**
* The Alt key extended modifier constant.
* @since 1.4
*/
public static final int ALT_DOWN_MASK = 1 << 9;
/**
* The Mouse Button1 extended modifier constant.
* @since 1.4
*/
public static final int BUTTON1_DOWN_MASK = 1 << 10;
/**
* The Mouse Button2 extended modifier constant.
* @since 1.4
*/
public static final int BUTTON2_DOWN_MASK = 1 << 11;
/**
* The Mouse Button3 extended modifier constant.
* @since 1.4
*/
public static final int BUTTON3_DOWN_MASK = 1 << 12;
/**
* The AltGraph key extended modifier constant.
* @since 1.4
*/
public static final int ALT_GRAPH_DOWN_MASK = 1 << 13;
static final int JDK_1_3_MODIFIERS = SHIFT_DOWN_MASK - 1;
/**
* The input event's Time stamp in UTC format. The time stamp
* indicates when the input event was created.
*
* @serial
* @see #getWhen()
*/
long when;
/**
* The state of the modifier mask at the time the input
* event was fired.
*
* @serial
* @see #getModifiers()
* @see #getModifiersEx()
* @see java.awt.event.KeyEvent
* @see java.awt.event.MouseEvent
*/
int modifiers;
/*
* A flag that indicates that this instance can be used to access
* the system clipboard.
*/
private transient boolean canAccessSystemClipboard;
static {
/* ensure that the necessary native libraries are loaded */
NativeLibLoader.loadLibraries();
if (!GraphicsEnvironment.isHeadless()) {
initIDs();
}
}
/**
* Initialize JNI field and method IDs for fields that may be
accessed from C.
*/
private static native void initIDs();
/**
* Constructs an InputEvent object with the specified source component,
* modifiers, and type.
* <p>Note that passing in an invalid <code>id</code> results in
* unspecified behavior. This method throws an
* <code>IllegalArgumentException</code> if <code>source</code>
* is <code>null</code>.
*
* @param source the object where the event originated
* @param id the event type
* @param when the time the event occurred
* @param modifiers represents the modifier keys and mouse buttons down
* while the event occurred
* @throws IllegalArgumentException if <code>source</code> is null
*/
InputEvent(Component source, int id, long when, int modifiers) {
super(source, id);
this.when = when;
this.modifiers = modifiers;
canAccessSystemClipboard = canAccessSystemClipboard();
}
private boolean canAccessSystemClipboard() {
boolean b = false;
if (!GraphicsEnvironment.isHeadless()) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
try {
sm.checkSystemClipboardAccess();
b = true;
} catch (SecurityException se) {
}
} else {
b = true;
}
}
return b;
}
/**
* Returns whether or not the Shift modifier is down on this event.
*/
public boolean isShiftDown() {
return (modifiers & SHIFT_MASK) != 0;
}
/**
* Returns whether or not the Control modifier is down on this event.
*/
public boolean isControlDown() {
return (modifiers & CTRL_MASK) != 0;
}
/**
* Returns whether or not the Meta modifier is down on this event.
*/
public boolean isMetaDown() {
return (modifiers & META_MASK) != 0;
}
/**
* Returns whether or not the Alt modifier is down on this event.
*/
public boolean isAltDown() {
return (modifiers & ALT_MASK) != 0;
}
/**
* Returns whether or not the AltGraph modifier is down on this event.
*/
public boolean isAltGraphDown() {
return (modifiers & ALT_GRAPH_MASK) != 0;
}
/**
* Returns the timestamp of when this event occurred.
*/
public long getWhen() {
return when;
}
/**
* Returns the modifier mask for this event.
*/
public int getModifiers() {
return modifiers & JDK_1_3_MODIFIERS;
}
/**
* Returns the extended modifier mask for this event.
* Extended modifiers represent the state of all modal keys,
* such as ALT, CTRL, META, and the mouse buttons just after
* the event occurred
* <P>
* For example, if the user presses <b>button 1</b> followed by
* <b>button 2</b>, and then releases them in the same order,
* the following sequence of events is generated:
* <PRE>
* <code>MOUSE_PRESSED</code>: <code>BUTTON1_DOWN_MASK</code>
* <code>MOUSE_PRESSED</code>: <code>BUTTON1_DOWN_MASK | BUTTON2_DOWN_MASK</code>
* <code>MOUSE_RELEASED</code>: <code>BUTTON2_DOWN_MASK</code>
* <code>MOUSE_CLICKED</code>: <code>BUTTON2_DOWN_MASK</code>
* <code>MOUSE_RELEASED</code>:
* <code>MOUSE_CLICKED</code>:
* </PRE>
* <P>
* It is not recommended to compare the return value of this method
* using <code>==</code> because new modifiers can be added in the future.
* For example, the appropriate way to check that SHIFT and BUTTON1 are
* down, but CTRL is up is demonstrated by the following code:
* <PRE>
* int onmask = SHIFT_DOWN_MASK | BUTTON1_DOWN_MASK;
* int offmask = CTRL_DOWN_MASK;
* if (event.getModifiersEx() & (onmask | offmask) == onmask) {
* ...
* }
* </PRE>
* The above code will work even if new modifiers are added.
*
* @since 1.4
*/
public int getModifiersEx() {
return modifiers & ~JDK_1_3_MODIFIERS;
}
/**
* Consumes this event so that it will not be processed
* in the default manner by the source which originated it.
*/
public void consume() {
consumed = true;
}
/**
* Returns whether or not this event has been consumed.
* @see #consume
*/
public boolean isConsumed() {
return consumed;
}
// state serialization compatibility with JDK 1.1
static final long serialVersionUID = -2482525981698309786L;
/**
* Returns a String describing the extended modifier keys and
* mouse buttons, such as "Shift", "Button1", or "Ctrl+Shift".
* These strings can be localized by changing the
* awt.properties file.
*
* @param modifiers a modifier mask describing the extended
* modifier keys and mouse buttons for the event
* @return a text description of the combination of extended
* modifier keys and mouse buttons that were held down
* during the event.
* @since 1.4
*/
public static String getModifiersExText(int modifiers) {
StringBuffer buf = new StringBuffer();
if ((modifiers & InputEvent.META_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.meta", "Meta"));
buf.append("+");
}
if ((modifiers & InputEvent.CTRL_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.control", "Ctrl"));
buf.append("+");
}
if ((modifiers & InputEvent.ALT_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.alt", "Alt"));
buf.append("+");
}
if ((modifiers & InputEvent.SHIFT_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.shift", "Shift"));
buf.append("+");
}
if ((modifiers & InputEvent.ALT_GRAPH_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.altGraph", "Alt Graph"));
buf.append("+");
}
if ((modifiers & InputEvent.BUTTON1_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.button1", "Button1"));
buf.append("+");
}
if ((modifiers & InputEvent.BUTTON2_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.button2", "Button2"));
buf.append("+");
}
if ((modifiers & InputEvent.BUTTON3_DOWN_MASK) != 0) {
buf.append(Toolkit.getProperty("AWT.button3", "Button3"));
buf.append("+");
}
if (buf.length() > 0) {
buf.setLength(buf.length()-1); // remove trailing '+'
}
return buf.toString();
}
}
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