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Human–ComPuter InteraCtIon
event classes possess additional specific attributes and associated
methods for accessing the values. For instance, the KeyEvent has
a method called getkeyChar that returns the value of the keyboard
input; the MouseEvent has methods called getPoint() and getClick-
Count() that return the screen-position data at which the mouse event
occurred and the number of clicks. For more detailed information, the
reader is referred to the reference manual for Java AWT [1].
Just like the event-component hierarchy, the event-listener interface
is also structured correspondingly, as seen in Figure6.3. A UI object,
possibly composed ...