29  * An abstract adapter class for receiving keyboard events.
  30  * The methods in this class are empty. This class exists as
  31  * convenience for creating listener objects.
  32  * <P>
  33  * Extend this class to create a <code>KeyEvent</code> listener
  34  * and override the methods for the events of interest. (If you implement the
  35  * <code>KeyListener</code> interface, you have to define all of
  36  * the methods in it. This abstract class defines null methods for them
  37  * all, so you can only have to define methods for events you care about.)
  38  * <P>
  39  * Create a listener object using the extended class and then register it with
  40  * a component using the component's <code>addKeyListener</code>
  41  * method. When a key is pressed, released, or typed,
  42  * the relevant method in the listener object is invoked,
  43  * and the <code>KeyEvent</code> is passed to it.
  44  *
  45  * @author Carl Quinn
  46  *
  47  * @see KeyEvent
  48  * @see KeyListener
  49  * @see <a href="http://java.sun.com/docs/books/tutorial/post1.0/ui/keylistener.html">Tutorial: Writing a Key Listener</a>
  50  *
  51  * @since 1.1
  52  */
  53 public abstract class KeyAdapter implements KeyListener {
  54     /**
  55      * Invoked when a key has been typed.
  56      * This event occurs when a key press is followed by a key release.
  57      */
  58     public void keyTyped(KeyEvent e) {}
  59 
  60     /**
  61      * Invoked when a key has been pressed.
  62      */
  63     public void keyPressed(KeyEvent e) {}
  64 
  65     /**
  66      * Invoked when a key has been released.
  67      */
  68     public void keyReleased(KeyEvent e) {}
  69 }

  29  * An abstract adapter class for receiving keyboard events.
  30  * The methods in this class are empty. This class exists as
  31  * convenience for creating listener objects.
  32  * <P>
  33  * Extend this class to create a <code>KeyEvent</code> listener
  34  * and override the methods for the events of interest. (If you implement the
  35  * <code>KeyListener</code> interface, you have to define all of
  36  * the methods in it. This abstract class defines null methods for them
  37  * all, so you can only have to define methods for events you care about.)
  38  * <P>
  39  * Create a listener object using the extended class and then register it with
  40  * a component using the component's <code>addKeyListener</code>
  41  * method. When a key is pressed, released, or typed,
  42  * the relevant method in the listener object is invoked,
  43  * and the <code>KeyEvent</code> is passed to it.
  44  *
  45  * @author Carl Quinn
  46  *
  47  * @see KeyEvent
  48  * @see KeyListener
  49  * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html">Tutorial: Writing a Key Listener</a>
  50  *
  51  * @since 1.1
  52  */
  53 public abstract class KeyAdapter implements KeyListener {
  54     /**
  55      * Invoked when a key has been typed.
  56      * This event occurs when a key press is followed by a key release.
  57      */
  58     public void keyTyped(KeyEvent e) {}
  59 
  60     /**
  61      * Invoked when a key has been pressed.
  62      */
  63     public void keyPressed(KeyEvent e) {}
  64 
  65     /**
  66      * Invoked when a key has been released.
  67      */
  68     public void keyReleased(KeyEvent e) {}
  69 }