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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package java.awt.event;
import java.util.EventListener;
/**
* The listener interface for receiving keyboard focus events on
* a component.
* The class that is interested in processing a focus event
* either implements this interface (and all the methods it
* contains) or extends the abstract <code>FocusAdapter</code> class
* (overriding only the methods of interest).
* The listener object created from that class is then registered with a
* component using the component's <code>addFocusListener</code>
* method. When the component gains or loses the keyboard focus,
* the relevant method in the listener object
* is invoked, and the <code>FocusEvent</code> is passed to it.
*
* @see FocusAdapter
* @see FocusEvent
* @see <a href="http://java.sun.com/docs/books/tutorial/post1.0/ui/focuslistener.html">Tutorial: Writing a Focus Listener</a>
*
* @author Carl Quinn
* @since 1.1
*/
public interface FocusListener extends EventListener {
/**
* Invoked when a component gains the keyboard focus.
*/
public void focusGained(FocusEvent e);
/**
* Invoked when a component loses the keyboard focus.
*/
public void focusLost(FocusEvent e);
}