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

All Implemented Interfaces:

Serializable

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.

Since:

1.1

See Also:

MouseAdapter, MouseListener, MouseMotionAdapter, MouseMotionListener, 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, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_EVENT_MASK, id, INPUT_METHOD_EVENT_MASK, INVOCATION_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, PAINT_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.

Overrides:

paramString in class ComponentEvent

Returns:

a string identifying the event and its attributes