java.awt.event
Class MouseEvent

java.lang.Object
  |
  +--java.util.EventObject
        |
        +--java.awt.AWTEvent
              |
              +--java.awt.event.ComponentEvent
                    |
                    +--java.awt.event.InputEvent
                          |
                          +--java.awt.event.MouseEvent

Direct Known Subclasses:

MenuDragMouseEvent

public class MouseEvent

extends InputEvent

/** An event which indicates that a mouse action occurred in a component. This event is used both for mouse events (click, enter, exit) and mouse motion events (moves and drags).

This low-level event is generated by a component object for:

• Mouse Events
  • a mouse button is pressed
  • a mouse button is released
  • a mouse button is clicked (pressed and released)
  • the mouse cursor enters a component
  • the mouse cursor exits a component
• Mouse Motion Events
  • the mouse is moved
  • the mouse is dragged

A MouseEvent object is passed to every MouseListener or MouseAdapter object which registered to receive the "interesting" mouse events using the component's addMouseListener method. (MouseAdapter objects implement the MouseListener interface.) Each such listener object gets a MouseEvent containing the mouse event.

A MouseEvent object is also passed to every MouseMotionListener or MouseMotionAdapter object which registered to receive mouse motion events using the component's addMouseMotionListener method. (MouseMotionAdapter objects implement the MouseMotionListener interface.) Each such listener object gets a MouseEvent containing the mouse motion event.

When a mouse button is clicked, events are generated and sent to the registered MouseListeners, with the button mask set in the modifier field. For example, if the first mouse button is pressed, events are sent in the following order:

    MOUSE_PRESSED:  BUTTON1_MASK
    MOUSE_RELEASED: BUTTON1_MASK
    MOUSE_CLICKED:  BUTTON1_MASK
 

When multiple mouse buttons are pressed, each press, release, and click results in a separate event. The button mask in the modifier field reflects only the button that changed state, not the current state of all buttons.

For example, if the user presses button 1 followed by button 2 and releases them in the same order, the following sequence of events is generated:

    MOUSE_PRESSED:  BUTTON1_MASK
    MOUSE_PRESSED:  BUTTON2_MASK
    MOUSE_RELEASED: BUTTON1_MASK
    MOUSE_CLICKED:  BUTTON1_MASK
    MOUSE_RELEASED: BUTTON2_MASK
    MOUSE_CLICKED:  BUTTON2_MASK
 
 If button2 is released first, the MOUSE_RELEASED/MOUSE_CLICKED pair
 for BUTTON2_MASK arrives first, followed by the pair for BUTTON1_MASK.


See Also: 
MouseAdapter, 
MouseListener, 
MouseMotionAdapter, 
MouseMotionListner, 
Tutorial: Writing a Mouse Listener, 
Tutorial: Writing a Mouse Motion Listener, 
Reference: The Java Class Libraries (update file), Serialized Form









Field Summary




static int
MOUSE_CLICKED



          The "mouse clicked" event.



static int
MOUSE_DRAGGED



          The "mouse dragged" event.



static int
MOUSE_ENTERED



          The "mouse entered" event.



static int
MOUSE_EXITED



          The "mouse exited" event.



static int
MOUSE_FIRST



          The first number in the range of ids used for mouse events.



static int
MOUSE_LAST



          The last number in the range of ids used for mouse events.



static int
MOUSE_MOVED



          The "mouse moved" event.



static int
MOUSE_PRESSED



          The "mouse pressed" event.



static int
MOUSE_RELEASED



          The "mouse released" event.


 
Fields inherited from class java.awt.event.InputEvent
ALT_GRAPH_MASK,  
ALT_MASK,  
BUTTON1_MASK,  
BUTTON2_MASK,  
BUTTON3_MASK,  
CTRL_MASK,  
META_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,  
consumed,  
CONTAINER_EVENT_MASK,  
FOCUS_EVENT_MASK,  
id,  
INPUT_METHOD_EVENT_MASK,  
ITEM_EVENT_MASK,  
KEY_EVENT_MASK,  
MOUSE_EVENT_MASK,  
MOUSE_MOTION_EVENT_MASK,  
RESERVED_ID_MAX,  
TEXT_EVENT_MASK,  
WINDOW_EVENT_MASK
 
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)



          Constructs a MouseEvent object with the specified source component,
 type, modifiers, coordinates, and click count.
 



Method Summary




 int
getClickCount()



          Return the number of mouse clicks associated with this event.



 Point
getPoint()



          Returns the x,y position of the event relative to the source component.



 int
getX()



          Returns the horizontal x position of the event relative to the 
 source component.



 int
getY()



          Returns the vertical y position of the event relative to the
 source component.



 boolean
isPopupTrigger()



          Returns whether or not this mouse event is the popup-menu
 trigger event for the platform.



 String
paramString()



          Returns a parameter string identifying this event.



 void
translatePoint(int x,
               int y)



          Translates the event's coordinates to a new position
 by adding specified x (horizontal) and y (veritcal) offsets.


 
Methods inherited from class java.awt.event.InputEvent
consume, 
getModifiers, 
getWhen, 
isAltDown, 
isAltGraphDown, 
isConsumed, 
isControlDown, 
isMetaDown, 
isShiftDown
 
Methods inherited from class java.awt.event.ComponentEvent
getComponent
 
Methods inherited from class java.awt.AWTEvent
finalize, 
getID, 
toString
 
Methods inherited from class java.util.EventObject
getSource
 
Methods inherited from class java.lang.Object
clone, 
equals, 
getClass, 
hashCode, 
notify, 
notifyAll, 
wait, 
wait, 
wait
 





Field Detail



MOUSE_FIRST
public static final int MOUSE_FIRST

The first number in the range of ids used for mouse events.



MOUSE_LAST
public static final int MOUSE_LAST

The last number in the range of ids used for mouse events.



MOUSE_CLICKED
public static final int MOUSE_CLICKED

The "mouse clicked" event. This MouseEvent occurs when a mouse
 button is pressed and released.



MOUSE_PRESSED
public static final int MOUSE_PRESSED

The "mouse pressed" event. This MouseEvent occurs when a mouse
 button is pushed down.



MOUSE_RELEASED
public static final int MOUSE_RELEASED

The "mouse released" event. This MouseEvent occurs when a mouse
 button is let up.



MOUSE_MOVED
public static final int MOUSE_MOVED

The "mouse moved" event. This MouseMotionEvent occurs when the mouse
 position changes.



MOUSE_ENTERED
public static final int MOUSE_ENTERED

The "mouse entered" event. This MouseEvent occurs when the mouse
 cursor enters a component's area.



MOUSE_EXITED
public static final int MOUSE_EXITED

The "mouse exited" event. This MouseEvent occurs when the mouse
 cursor leaves a component's area.



MOUSE_DRAGGED
public static final int MOUSE_DRAGGED

The "mouse dragged" event. This MouseMotionEvent occurs when the mouse
 position changes while the "drag" modifier is active (for example, the
 shift key).




Constructor Detail



MouseEvent
public MouseEvent(Component source,
                  int id,
                  long when,
                  int modifiers,
                  int x,
                  int y,
                  int clickCount,
                  boolean popupTrigger)

Constructs a MouseEvent object with the specified source component,
 type, modifiers, coordinates, and click count.

Parameters:
source - the Component that originated the event
id - the integer that identifies the event
when - a long int that gives the time the event occurred
modifiers - the modifier keys down during event
                     (shift, ctrl, alt, meta)
x - the horizontal x coordinate for the mouse location
y - the vertical y coordinate for the mouse location
clickCount - the number of mouse clicks associated with event
popupTrigger - a boolean, true if this event is a trigger for a
                     popup-menu






Method Detail



getX
public int getX()

Returns the horizontal x position of the event relative to the 
 source component.

Returns:
x  an integer indicating horizontal position relative to
            the component





getY
public int getY()

Returns the vertical y position of the event relative to the
 source component.

Returns:
y  an integer indicating vertical position relative to
            the component





getPoint
public Point getPoint()

Returns the x,y position of the event relative to the source component.

Returns:
a Point object containing the x and y coordinates 
         relative to the source component





translatePoint
public void translatePoint(int x,
                           int y)

Translates the event's coordinates to a new position
 by adding specified x (horizontal) and y (veritcal) offsets.

Parameters:
x - the horizontal x value to add to the current x coordinate position
y - the vertical y value to add to the current y coordinate position





getClickCount
public int getClickCount()

Return the number of mouse clicks associated with this event.

Returns:
integer value for the number of clicks





isPopupTrigger
public boolean isPopupTrigger()

Returns whether or not this mouse event is the popup-menu
 trigger event for the platform.

Returns:
boolean, true if this event is the popup-menu trigger
         for this platform





paramString
public String paramString()

Returns a parameter string identifying this event.
 This method is useful for event-logging and for debugging.

Returns:
a string identifying the event and its attributes
Overrides:
paramString in class ComponentEvent