/*

 * Copyright 1997-2003 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.swing;

import java.awt.Component;

import java.awt.Container;

import java.awt.FocusTraversalPolicy;

import java.util.Comparator;

/**

 * This class has been obsoleted by the 1.4 focus APIs. While client code may

 * still use this class, developers are strongly encouraged to use

 * <code>java.awt.KeyboardFocusManager</code> and

 * <code>java.awt.DefaultKeyboardFocusManager</code> instead.

 * <p>

 * Please see

 * <a href="http://java.sun.com/docs/books/tutorial/uiswing/misc/focus.html">

 * How to Use the Focus Subsystem</a>,

 * a section in <em>The Java Tutorial</em>, and the

 * <a href="../../java/awt/doc-files/FocusSpec.html">Focus Specification</a>

 * for more information.

 *

 * @author Arnaud Weber

 * @author David Mendenhall

 */

public class DefaultFocusManager extends FocusManager {

    final FocusTraversalPolicy gluePolicy =

        new LegacyGlueFocusTraversalPolicy(this);

    private final FocusTraversalPolicy layoutPolicy =

        new LegacyLayoutFocusTraversalPolicy(this);

    private final LayoutComparator comparator =

        new LayoutComparator();

    public DefaultFocusManager() {

        setDefaultFocusTraversalPolicy(gluePolicy);

    }

    public Component getComponentAfter(Container aContainer,

                                       Component aComponent)

    {

        Container root = (aContainer.isFocusCycleRoot())

            ? aContainer

            : aContainer.getFocusCycleRootAncestor();

        // Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's

        // traversal policy is non-legacy, then honor it.

        if (root != null) {

            FocusTraversalPolicy policy = root.getFocusTraversalPolicy();

            if (policy != gluePolicy) {

                return policy.getComponentAfter(root, aComponent);

            }

            comparator.setComponentOrientation(root.getComponentOrientation());

            return layoutPolicy.getComponentAfter(root, aComponent);

        }

        return null;

    }

    public Component getComponentBefore(Container aContainer,

                                        Component aComponent)

    {

        Container root = (aContainer.isFocusCycleRoot())

            ? aContainer

            : aContainer.getFocusCycleRootAncestor();

        // Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's

        // traversal policy is non-legacy, then honor it.

        if (root != null) {

            FocusTraversalPolicy policy = root.getFocusTraversalPolicy();

            if (policy != gluePolicy) {

                return policy.getComponentBefore(root, aComponent);

            }

            comparator.setComponentOrientation(root.getComponentOrientation());

            return layoutPolicy.getComponentBefore(root, aComponent);

        }

        return null;

    }

    public Component getFirstComponent(Container aContainer) {

        Container root = (aContainer.isFocusCycleRoot())

            ? aContainer

            : aContainer.getFocusCycleRootAncestor();

        // Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's

        // traversal policy is non-legacy, then honor it.

        if (root != null) {

            FocusTraversalPolicy policy = root.getFocusTraversalPolicy();

            if (policy != gluePolicy) {

                return policy.getFirstComponent(root);

            }

            comparator.setComponentOrientation(root.getComponentOrientation());

            return layoutPolicy.getFirstComponent(root);

        }

        return null;

    }

    public Component getLastComponent(Container aContainer) {

        Container root = (aContainer.isFocusCycleRoot())

            ? aContainer

            : aContainer.getFocusCycleRootAncestor();

        // Support for mixed 1.4/pre-1.4 focus APIs. If a particular root's

        // traversal policy is non-legacy, then honor it.

        if (root != null) {

            FocusTraversalPolicy policy = root.getFocusTraversalPolicy();

            if (policy != gluePolicy) {

                return policy.getLastComponent(root);

            }

            comparator.setComponentOrientation(root.getComponentOrientation());

            return layoutPolicy.getLastComponent(root);

        }

        return null;

    }

    public boolean compareTabOrder(Component a, Component b) {

        return (comparator.compare(a, b) < 0);

    }

}

final class LegacyLayoutFocusTraversalPolicy

    extends LayoutFocusTraversalPolicy

{

    LegacyLayoutFocusTraversalPolicy(DefaultFocusManager defaultFocusManager) {

        super(new CompareTabOrderComparator(defaultFocusManager));

    }

}

final class CompareTabOrderComparator implements Comparator {

    private final DefaultFocusManager defaultFocusManager;

    CompareTabOrderComparator(DefaultFocusManager defaultFocusManager) {

        this.defaultFocusManager = defaultFocusManager;

    }

    public int compare(Object o1, Object o2) {

        if (o1 == o2) {

            return 0;

        }

        return (defaultFocusManager.compareTabOrder((Component)o1,

                                                    (Component)o2)) ? -1 : 1;

    }

}