/*

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * 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.

 *

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package java.awt.dnd;

import java.awt.Insets;

import java.awt.Point;

/**

 * During DnD operations it is possible that a user may wish to drop the

 * subject of the operation on a region of a scrollable GUI control that is

 * not currently visible to the user.

 * <p>

 * In such situations it is desirable that the GUI control detect this

 * and institute a scroll operation in order to make obscured region(s)

 * visible to the user. This feature is known as autoscrolling.

 * <p>

 * If a GUI control is both an active <code>DropTarget</code>

 * and is also scrollable, it

 * can receive notifications of autoscrolling gestures by the user from

 * the DnD system by implementing this interface.

 * <p>

 * An autoscrolling gesture is initiated by the user by keeping the drag

 * cursor motionless with a border region of the <code>Component</code>,

 * referred to as

 * the "autoscrolling region", for a predefined period of time, this will

 * result in repeated scroll requests to the <code>Component</code>

 * until the drag <code>Cursor</code> resumes its motion.

 *

 * @since 1.2

 */

public interface Autoscroll {

    /**

     * This method returns the <code>Insets</code> describing

     * the autoscrolling region or border relative

     * to the geometry of the implementing Component.

     * <P>

     * This value is read once by the <code>DropTarget</code>

     * upon entry of the drag <code>Cursor</code>

     * into the associated <code>Component</code>.

     * <P>

     * @return the Insets

     */

    public Insets getAutoscrollInsets();

    /**

     * notify the <code>Component</code> to autoscroll

     * <P>

     * @param cursorLocn A <code>Point</code> indicating the

     * location of the cursor that triggered this operation.

     */

    public void autoscroll(Point cursorLocn);

}