/* * Copyright (c) 2000, 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 javax.swing;  import java.awt.Component;import java.awt.FocusTraversalPolicy; /** * A FocusTraversalPolicy which can optionally provide an algorithm for * determining a JInternalFrame's initial Component. The initial Component is * the first to receive focus when the JInternalFrame is first selected. By * default, this is the same as the JInternalFrame's default Component to * focus. * * @author David Mendenhall * * @since 1.4 */public abstract class InternalFrameFocusTraversalPolicy    extends FocusTraversalPolicy{     /**     * Returns the Component that should receive the focus when a     * JInternalFrame is selected for the first time. Once the JInternalFrame     * has been selected by a call to <code>setSelected(true)</code>, the     * initial Component will not be used again. Instead, if the JInternalFrame     * loses and subsequently regains selection, or is made invisible or     * undisplayable and subsequently made visible and displayable, the     * JInternalFrame's most recently focused Component will become the focus     * owner. The default implementation of this method returns the     * JInternalFrame's default Component to focus.     *     * @param frame the JInternalFrame whose initial Component is to be     *        returned     * @return the Component that should receive the focus when frame is     *         selected for the first time, or null if no suitable Component     *         can be found     * @see JInternalFrame#getMostRecentFocusOwner     * @throws IllegalArgumentException if window is null     */    public Component getInitialComponent(JInternalFrame frame) {        return getDefaultComponent(frame);    }}