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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
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
* 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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package java.awt;
import java.awt.event.KeyEvent;
/**
* A KeyEventPostProcessor cooperates with the current KeyboardFocusManager
* in the final resolution of all unconsumed KeyEvents. KeyEventPostProcessors
* registered with the current KeyboardFocusManager will receive KeyEvents
* after the KeyEvents have been dispatched to and handled by their targets.
* KeyEvents that would have been otherwise discarded because no Component in
* the application currently owns the focus will also be forwarded to
* registered KeyEventPostProcessors. This will allow applications to implement
* features that require global KeyEvent post-handling, such as menu shortcuts.
* <p>
* Note that the KeyboardFocusManager itself implements KeyEventPostProcessor.
* By default, the current KeyboardFocusManager will be the final
* KeyEventPostProcessor in the chain. The current KeyboardFocusManager cannot
* be completely deregistered as a KeyEventPostProcessor. However, if a
* KeyEventPostProcessor reports that no further post-processing of the
* KeyEvent should take place, the AWT will consider the event fully handled
* and will take no additional action with regard to the event. (While it is
* possible for client code to register the current KeyboardFocusManager as
* a KeyEventPostProcessor one or more times, this is usually unnecessary and
* not recommended.)
*
* @author David Mendenhall
*
* @see KeyboardFocusManager#addKeyEventPostProcessor
* @see KeyboardFocusManager#removeKeyEventPostProcessor
* @since 1.4
*/
public interface KeyEventPostProcessor {
/**
* This method is called by the current KeyboardFocusManager, requesting
* that this KeyEventPostProcessor perform any necessary post-processing
* which should be part of the KeyEvent's final resolution. At the time
* this method is invoked, typically the KeyEvent has already been
* dispatched to and handled by its target. However, if no Component in
* the application currently owns the focus, then the KeyEvent has not
* been dispatched to any Component. Typically, KeyEvent post-processing
* will be used to implement features which require global KeyEvent
* post-handling, such as menu shortcuts. Note that if a
* KeyEventPostProcessor wishes to dispatch the KeyEvent, it must use
* <code>redispatchEvent</code> to prevent the AWT from recursively
* requesting that this KeyEventPostProcessor perform post-processing
* of the event again.
* <p>
* If an implementation of this method returns <code>false</code>, then the
* KeyEvent is passed to the next KeyEventPostProcessor in the chain,
* ending with the current KeyboardFocusManager. If an implementation
* returns <code>true</code>, the KeyEvent is assumed to have been fully
* handled (although this need not be the case), and the AWT will take no
* further action with regard to the KeyEvent. If an implementation
* consumes the KeyEvent but returns <code>false</code>, the consumed
* event will still be passed to the next KeyEventPostProcessor in the
* chain. It is important for developers to check whether the KeyEvent has
* been consumed before performing any post-processing of the KeyEvent. By
* default, the current KeyboardFocusManager will perform no post-
* processing in response to a consumed KeyEvent.
*
* @param e the KeyEvent to post-process
* @return <code>true</code> if the AWT should take no further action with
* regard to the KeyEvent; <code>false</code> otherwise
* @see KeyboardFocusManager#redispatchEvent
*/
boolean postProcessKeyEvent(KeyEvent e);
}