/*

 * Copyright (c) 2009, 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 sun.swing;

import sun.misc.Unsafe;

import java.awt.Point;

import javax.swing.text.JTextComponent;

import javax.swing.TransferHandler;

/**

 * The SwingAccessor utility class.

 * The main purpose of this class is to enable accessing

 * private and package-private fields of classes from

 * different classes/packages. See sun.misc.SharedSecretes

 * for another example.

 */

public final class SwingAccessor {

    private static final Unsafe unsafe = Unsafe.getUnsafe();

    /**

     * We don't need any objects of this class.

     * It's rather a collection of static methods

     * and interfaces.

     */

    private SwingAccessor() {

    }

    /**

     * An accessor for the JTextComponent class.

     * Note that we intentionally introduce the JTextComponentAccessor,

     * and not the JComponentAccessor because the needed methods

     * aren't override methods.

     */

    public interface JTextComponentAccessor {

        /**

         * Calculates a custom drop location for the text component,

         * representing where a drop at the given point should insert data.

         */

        TransferHandler.DropLocation dropLocationForPoint(JTextComponent textComp, Point p);

        /**

         * Called to set or clear the drop location during a DnD operation.

         */

        Object setDropLocation(JTextComponent textComp, TransferHandler.DropLocation location,

                               Object state, boolean forDrop);

    }

    /**

     * The javax.swing.text.JTextComponent class accessor object.

     */

    private static JTextComponentAccessor jtextComponentAccessor;

    /**

     * Set an accessor object for the javax.swing.text.JTextComponent class.

     */

    public static void setJTextComponentAccessor(JTextComponentAccessor jtca) {

         jtextComponentAccessor = jtca;

    }

    /**

     * Retrieve the accessor object for the javax.swing.text.JTextComponent class.

     */

    public static JTextComponentAccessor getJTextComponentAccessor() {

        if (jtextComponentAccessor == null) {

            unsafe.ensureClassInitialized(JTextComponent.class);

        }

        return jtextComponentAccessor;

    }

}