Graphical User Interfaces - JavaTech: An Introduction to Scientific and Technical Computing with Java - page 209

java.lang.Object
+-java.util.EventObject
+-java.awt.AWTEvent
+-java.awt.event.ComponentEvent
+-java.awt.event.InputEvent
+-java.awt.event.MouseEvent
These include a number of methods that provide information about an event. (See
the Java 2 API Specification for a detailed listing.) A sampling of the methods
include:
getComponent () - identifies the Component object that generated the event
getX () , getY () , getPoint () - provide the coordinates of the mouse location
getClickCount () -gives number of times the mouse button was clicked
getModifiers () - indicates what modifier keys were held down during the event
Both the motion of the mouse and its buttons create events. There are two
separate types of mouse event listeners:
MouseMotionListener
Each move of the mouse generates a motion event. To listen for mouse motion events,
a class needs to implement the MouseMotionListener interface. The implementing
class will need to provide two methods:
mouseMoved (MouseEvent e) - mouse motion
mouseDragged (MouseEvent e) - mouse motion when mouse button is held
down
MouseListener
The MouseListener interface provides these methods for mouse button and cursor
events:
mousePressed (MouseEvent e) - mouse button is pressed
mouseReleased (MouseEvent e) - mouse button is released
mouseClicked (MouseEvent e) -button clicked (press and release counts as
one action)
mouseEntered (MouseEvent e) - the cursor enters the area of the component
mouseExited (MouseEvent e) - the cursor exits the area of the component
The following example program CaptureEvtApplet illustrates how to use the
MouseListener interface to monitor when a mouse cursor enters or exits the
area of the panel and when clicks are made over the panel. The program displays
messages in a JTextArea to indicate the different ways that mouse events