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package java.awt.event;


An abstract adapter class for receiving keyboard focus events.
The methods in this class are empty. This class exists as
convenience for creating listener objects.

 Extend this class to create a FocusEvent listener and override the methods for the events of interest. (If you implement the FocusListener interface, you have to define all of the methods in it. This abstract class defines null methods for them all, so you can only have to define methods for events you care about.) 
 Create a listener object using the extended class and then register it with a component using the component's addFocusListener method. When the component gains or loses the keyboard focus, the relevant method in the listener object is invoked, and the FocusEvent is passed to it. 
Author:Carl Quinn
See Also:
Since:1.1
/**
 * An abstract adapter class for receiving keyboard focus events.
 * The methods in this class are empty. This class exists as
 * convenience for creating listener objects.
 * <P>
 * Extend this class to create a {@code FocusEvent} listener
 * and override the methods for the events of interest. (If you implement the
 * {@code FocusListener} interface, you have to define all of
 * the methods in it. This abstract class defines null methods for them
 * all, so you can only have to define methods for events you care about.)
 * <P>
 * Create a listener object using the extended class and then register it with
 * a component using the component's {@code addFocusListener}
 * method. When the component gains or loses the keyboard focus,
 * the relevant method in the listener object is invoked,
 * and the {@code FocusEvent} is passed to it.
 *
 * @see FocusEvent
 * @see FocusListener
 * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/focuslistener.html">Tutorial: Writing a Focus Listener</a>
 *
 * @author Carl Quinn
 * @since 1.1
 */
public abstract class FocusAdapter implements FocusListener {
    
Invoked when a component gains the keyboard focus.

/**
     * Invoked when a component gains the keyboard focus.
     */
    public void focusGained(FocusEvent e) {}

    
Invoked when a component loses the keyboard focus.

/**
     * Invoked when a component loses the keyboard focus.
     */
    public void focusLost(FocusEvent e) {}
}