java.awt.event

Class MouseEvent

Implemented Interfaces:
Serializable
Known Direct Subclasses:
MenuDragMouseEvent, MouseWheelEvent

public class MouseEvent
extends InputEvent

This event is generated for a mouse event. There are three main categories of mouse events: Regular events include pressing, releasing, and clicking buttons, as well as moving over the boundary of the unobscured portion of a component. Motion events include movement and dragging. Wheel events are covered separately by the subclass MouseWheelEvent.

A mouse event is tied to the unobstructed visible component that the mouse cursor was over at the time of the action. The button that was most recently pressed is the only one that shows up in getModifiers, and is returned by getButton, while all buttons that are down show up in getModifiersEx.

Drag events may be cut short if native drag-and-drop operations steal the event. Likewise, if a mouse drag exceeds the bounds of a window or virtual device, some platforms may clip the path to fit in the bounds of the component.

Since:
1.1
See Also:
MouseAdapter, MouseListener, MouseMotionAdapter, MouseMotionListener, MouseWheelListener, Serialized Form

Field Summary

static int
BUTTON1
This indicates that button 1 changed state.
static int
BUTTON2
This indicates that button 2 changed state.
static int
BUTTON3
This indicates that button 3 changed state.
static int
MOUSE_CLICKED
This event id indicates that the mouse was clicked.
static int
MOUSE_DRAGGED
This event id indicates that the mouse was dragged over a component.
static int
MOUSE_ENTERED
This event id indicates that the mouse entered a component.
static int
MOUSE_EXITED
This event id indicates that the mouse exited a component.
static int
MOUSE_FIRST
This is the first id in the range of event ids used by this class.
static int
MOUSE_LAST
This is the last id in the range of event ids used by this class.
static int
MOUSE_MOVED
This event id indicates that the mouse was moved.
static int
MOUSE_PRESSED
This event id indicates that the mouse was pressed.
static int
MOUSE_RELEASED
This event id indicates that the mouse was released.
static int
MOUSE_WHEEL
This event id indicates that the mouse wheel was rotated.
static int
NOBUTTON
This indicates that no button changed state.

Fields inherited from class java.awt.event.InputEvent

ALT_DOWN_MASK, ALT_GRAPH_DOWN_MASK, ALT_GRAPH_MASK, ALT_MASK, BUTTON1_DOWN_MASK, BUTTON1_MASK, BUTTON2_DOWN_MASK, BUTTON2_MASK, BUTTON3_DOWN_MASK, BUTTON3_MASK, CTRL_DOWN_MASK, CTRL_MASK, META_DOWN_MASK, META_MASK, SHIFT_DOWN_MASK, SHIFT_MASK

Fields inherited from class java.awt.event.ComponentEvent

COMPONENT_FIRST, COMPONENT_HIDDEN, COMPONENT_LAST, COMPONENT_MOVED, COMPONENT_RESIZED, COMPONENT_SHOWN

Fields inherited from class java.awt.AWTEvent

ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_EVENT_MASK, INPUT_METHOD_EVENT_MASK, INVOCATION_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, MOUSE_WHEEL_EVENT_MASK, PAINT_EVENT_MASK, RESERVED_ID_MAX, TEXT_EVENT_MASK, WINDOW_EVENT_MASK, WINDOW_FOCUS_EVENT_MASK, WINDOW_STATE_EVENT_MASK, consumed, id

Fields inherited from class java.util.EventObject

source

Constructor Summary

MouseEvent(Component source, int id, long when, int modifiers, int x, int y, int clickCount, boolean popupTrigger)
Initializes a new instance of MouseEvent with the specified information.
MouseEvent(Component source, int id, long when, int modifiers, int x, int y, int clickCount, boolean popupTrigger, int button)
Initializes a new instance of MouseEvent with the specified information.
MouseEvent(Component source, int id, long when, int modifiers, int x, int y, int absX, int absY, int clickCount, boolean popupTrigger, int button)
Creates a new MouseEvent.

Method Summary

int
getButton()
Returns which button, if any, was the most recent to change state.
int
getClickCount()
This method returns the number of mouse clicks associated with this event.
Point
getLocationOnScreen()
static String
getMouseModifiersText(int modifiers)
Returns a string describing the modifiers, such as "Shift" or "Ctrl+Button1".
Point
getPoint()
This method returns a Point for the x,y position of the mouse pointer.
int
getX()
This method returns the X coordinate of the mouse position.
int
getXOnScreen()
int
getY()
This method returns the Y coordinate of the mouse position.
int
getYOnScreen()
boolean
isPopupTrigger()
This method tests whether or not the event is a popup menu trigger.
String
paramString()
Returns a string identifying this event.
void
translatePoint(int dx, int dy)
Translates the event coordinates by the specified x and y offsets.

Methods inherited from class java.awt.event.InputEvent

consume, getModifiers, getModifiersEx, getModifiersExText, getWhen, isAltDown, isAltGraphDown, isConsumed, isControlDown, isMetaDown, isShiftDown

Methods inherited from class java.awt.event.ComponentEvent

getComponent, paramString

Methods inherited from class java.awt.AWTEvent

consume, getID, isConsumed, paramString, setSource, toString

Methods inherited from class java.util.EventObject

getSource, toString

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

BUTTON1

public static final int BUTTON1
This indicates that button 1 changed state.
Field Value:
1
Since:
1.4
See Also:
getButton()

BUTTON2

public static final int BUTTON2
This indicates that button 2 changed state.
Field Value:
2
Since:
1.4
See Also:
getButton()

BUTTON3

public static final int BUTTON3
This indicates that button 3 changed state.
Field Value:
3
Since:
1.4
See Also:
getButton()

MOUSE_CLICKED

public static final int MOUSE_CLICKED
This event id indicates that the mouse was clicked.
Field Value:
500

MOUSE_DRAGGED

public static final int MOUSE_DRAGGED
This event id indicates that the mouse was dragged over a component.
Field Value:
506

MOUSE_ENTERED

public static final int MOUSE_ENTERED
This event id indicates that the mouse entered a component.
Field Value:
504

MOUSE_EXITED

public static final int MOUSE_EXITED
This event id indicates that the mouse exited a component.
Field Value:
505

MOUSE_FIRST

public static final int MOUSE_FIRST
This is the first id in the range of event ids used by this class.
Field Value:
500

MOUSE_LAST

public static final int MOUSE_LAST
This is the last id in the range of event ids used by this class.
Field Value:
507

MOUSE_MOVED

public static final int MOUSE_MOVED
This event id indicates that the mouse was moved.
Field Value:
503

MOUSE_PRESSED

public static final int MOUSE_PRESSED
This event id indicates that the mouse was pressed.
Field Value:
501

MOUSE_RELEASED

public static final int MOUSE_RELEASED
This event id indicates that the mouse was released.
Field Value:
502

MOUSE_WHEEL

public static final int MOUSE_WHEEL
This event id indicates that the mouse wheel was rotated.
Field Value:
507
Since:
1.4

NOBUTTON

public static final int NOBUTTON
This indicates that no button changed state.
Field Value:
0
Since:
1.4
See Also:
getButton()

Constructor Details

MouseEvent

public MouseEvent(Component source,
                  int id,
                  long when,
                  int modifiers,
                  int x,
                  int y,
                  int clickCount,
                  boolean popupTrigger)
Initializes a new instance of MouseEvent with the specified information. Note that an invalid id leads to unspecified results.
Parameters:
source - the source of the event
id - the event id
when - the timestamp of when the event occurred
modifiers - the modifier keys during the event, in old or new style
x - the X coordinate of the mouse point
y - the Y coordinate of the mouse point
clickCount - the number of mouse clicks for this event
popupTrigger - true if this event triggers a popup menu
Throws:
IllegalArgumentException - if source is null

MouseEvent

public MouseEvent(Component source,
                  int id,
                  long when,
                  int modifiers,
                  int x,
                  int y,
                  int clickCount,
                  boolean popupTrigger,
                  int button)
Initializes a new instance of MouseEvent with the specified information. Note that an invalid id leads to unspecified results.
Parameters:
source - the source of the event
id - the event id
when - the timestamp of when the event occurred
modifiers - the modifier keys during the event, in old or new style
x - the X coordinate of the mouse point
y - the Y coordinate of the mouse point
clickCount - the number of mouse clicks for this event
popupTrigger - true if this event triggers a popup menu
button - the most recent mouse button to change state
Throws:
IllegalArgumentException - if source is null or button is invalid
Since:
1.4

MouseEvent

public MouseEvent(Component source,
                  int id,
                  long when,
                  int modifiers,
                  int x,
                  int y,
                  int absX,
                  int absY,
                  int clickCount,
                  boolean popupTrigger,
                  int button)
Creates a new MouseEvent. This is like the other constructors and adds specific absolute coordinates.
Parameters:
source - the source of the event
id - the event id
when - the timestamp of when the event occurred
modifiers - the modifier keys during the event, in old or new style
x - the X coordinate of the mouse point
y - the Y coordinate of the mouse point
absX - the absolute X screen coordinate of this event
absY - the absolute Y screen coordinate of this event
clickCount - the number of mouse clicks for this event
popupTrigger - true if this event triggers a popup menu
button - the most recent mouse button to change state
Throws:
IllegalArgumentException - if source is null or button is invalid
Since:
1.6

Method Details

getButton

public int getButton()
Returns which button, if any, was the most recent to change state. This will be one of NOBUTTON, BUTTON1, BUTTON2, or BUTTON3.
Returns:
the button that changed state
Since:
1.4

getClickCount

public int getClickCount()
This method returns the number of mouse clicks associated with this event.
Returns:
the number of mouse clicks for this event

getLocationOnScreen

public Point getLocationOnScreen()
Since:
1.6

getMouseModifiersText

public static String getMouseModifiersText(int modifiers)
Returns a string describing the modifiers, such as "Shift" or "Ctrl+Button1". XXX Sun claims this can be localized via the awt.properties file - how do we implement that?
Parameters:
modifiers - the old-style modifiers to convert to text
Returns:
a string representation of the modifiers in this bitmask

getPoint

public Point getPoint()
This method returns a Point for the x,y position of the mouse pointer. This is relative to the source component.
Returns:
a Point for the event position

getX

public int getX()
This method returns the X coordinate of the mouse position. This is relative to the source component.
Returns:
the x coordinate

getXOnScreen

public int getXOnScreen()
Since:
1.6

getY

public int getY()
This method returns the Y coordinate of the mouse position. This is relative to the source component.
Returns:
the y coordinate

getYOnScreen

public int getYOnScreen()
Since:
1.6

isPopupTrigger

public boolean isPopupTrigger()
This method tests whether or not the event is a popup menu trigger. This should be checked in both MousePressed and MouseReleased to be cross-platform compatible, as different systems have different popup triggers.
Returns:
true if the event is a popup menu trigger

paramString

public String paramString()
Returns a string identifying this event. This is formatted as the field name of the id type, followed by the (x,y) point, the most recent button changed, modifiers (if any), extModifiers (if any), and clickCount.
Overrides:
paramString in interface ComponentEvent
Returns:
a string identifying this event

translatePoint

public void translatePoint(int dx,
                           int dy)
Translates the event coordinates by the specified x and y offsets.
Parameters:
dx - the value to add to the X coordinate of this event
dy - the value to add to the Y coordiante of this event

MouseEvent.java -- a mouse event Copyright (C) 1999, 2002, 2004, 2005 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.