| /* |
| * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * 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. |
| * |
| * 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). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package java.awt; |
| |
| import java.awt.event.KeyEvent; |
| |
| |
| /** |
| * A KeyEventDispatcher cooperates with the current KeyboardFocusManager in the |
| * targeting and dispatching of all KeyEvents. KeyEventDispatchers registered |
| * with the current KeyboardFocusManager will receive KeyEvents before they are |
| * dispatched to their targets, allowing each KeyEventDispatcher to retarget |
| * the event, consume it, dispatch the event itself, or make other changes. |
| * <p> |
| * Note that KeyboardFocusManager itself implements KeyEventDispatcher. By |
| * default, the current KeyboardFocusManager will be the sink for all KeyEvents |
| * not dispatched by the registered KeyEventDispatchers. The current |
| * KeyboardFocusManager cannot be completely deregistered as a |
| * KeyEventDispatcher. However, if a KeyEventDispatcher reports that it |
| * dispatched the KeyEvent, regardless of whether it actually did so, the |
| * KeyboardFocusManager will take no further action with regard to the |
| * KeyEvent. (While it is possible for client code to register the current |
| * KeyboardFocusManager as a KeyEventDispatcher one or more times, this is |
| * usually unnecessary and not recommended.) |
| * |
| * @author David Mendenhall |
| * |
| * @see KeyboardFocusManager#addKeyEventDispatcher |
| * @see KeyboardFocusManager#removeKeyEventDispatcher |
| * @since 1.4 |
| */ |
| @FunctionalInterface |
| public interface KeyEventDispatcher { |
| |
| /** |
| * This method is called by the current KeyboardFocusManager requesting |
| * that this KeyEventDispatcher dispatch the specified event on its behalf. |
| * This KeyEventDispatcher is free to retarget the event, consume it, |
| * dispatch it itself, or make other changes. This capability is typically |
| * used to deliver KeyEvents to Components other than the focus owner. This |
| * can be useful when navigating children of non-focusable Windows in an |
| * accessible environment, for example. Note that if a KeyEventDispatcher |
| * dispatches the KeyEvent itself, it must use {@code redispatchEvent} |
| * to prevent the current KeyboardFocusManager from recursively requesting |
| * that this KeyEventDispatcher dispatch the event again. |
| * <p> |
| * If an implementation of this method returns {@code false}, then |
| * the KeyEvent is passed to the next KeyEventDispatcher in the chain, |
| * ending with the current KeyboardFocusManager. If an implementation |
| * returns {@code true}, the KeyEvent is assumed to have been |
| * dispatched (although this need not be the case), and the current |
| * KeyboardFocusManager will take no further action with regard to the |
| * KeyEvent. In such a case, |
| * {@code KeyboardFocusManager.dispatchEvent} should return |
| * {@code true} as well. If an implementation consumes the KeyEvent, |
| * but returns {@code false}, the consumed event will still be passed |
| * to the next KeyEventDispatcher in the chain. It is important for |
| * developers to check whether the KeyEvent has been consumed before |
| * dispatching it to a target. By default, the current KeyboardFocusManager |
| * will not dispatch a consumed KeyEvent. |
| * |
| * @param e the KeyEvent to dispatch |
| * @return {@code true} if the KeyboardFocusManager should take no |
| * further action with regard to the KeyEvent; {@code false} |
| * otherwise |
| * @see KeyboardFocusManager#redispatchEvent |
| */ |
| boolean dispatchKeyEvent(KeyEvent e); |
| } |