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 * 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

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 */

package java.awt.dnd;

import java.awt.Component;

import java.awt.event.MouseEvent;

import java.awt.event.MouseListener;

import java.awt.event.MouseMotionListener;

/**

 * This abstract subclass of <code>DragGestureRecognizer</code>

 * defines a <code>DragGestureRecognizer</code>

 * for mouse-based gestures.

 *

 * Each platform implements its own concrete subclass of this class,

 * available via the Toolkit.createDragGestureRecognizer() method,

 * to encapsulate

 * the recognition of the platform dependent mouse gesture(s) that initiate

 * a Drag and Drop operation.

 * <p>

 * Mouse drag gesture recognizers should honor the

 * drag gesture motion threshold, available through

 * {@link DragSource#getDragThreshold}.

 * A drag gesture should be recognized only when the distance

 * in either the horizontal or vertical direction between

 * the location of the latest mouse dragged event and the

 * location of the corresponding mouse button pressed event

 * is greater than the drag gesture motion threshold.

 * <p>

 * Drag gesture recognizers created with

 * {@link DragSource#createDefaultDragGestureRecognizer}

 * follow this convention.

 *

 * @author Laurence P. G. Cable

 *

 * @see java.awt.dnd.DragGestureListener

 * @see java.awt.dnd.DragGestureEvent

 * @see java.awt.dnd.DragSource

 */

public abstract class MouseDragGestureRecognizer extends DragGestureRecognizer implements MouseListener, MouseMotionListener {

    private static final long serialVersionUID = 6220099344182281120L;

    /**

     * Construct a new <code>MouseDragGestureRecognizer</code>

     * given the <code>DragSource</code> for the

     * <code>Component</code> c, the <code>Component</code>

     * to observe, the action(s)

     * permitted for this drag operation, and

     * the <code>DragGestureListener</code> to

     * notify when a drag gesture is detected.

     * @param ds  The DragSource for the Component c

     * @param c   The Component to observe

     * @param act The actions permitted for this Drag

     * @param dgl The DragGestureListener to notify when a gesture is detected

     *

     */

    protected MouseDragGestureRecognizer(DragSource ds, Component c, int act, DragGestureListener dgl) {

        super(ds, c, act, dgl);

    }

    /**

     * Construct a new <code>MouseDragGestureRecognizer</code>

     * given the <code>DragSource</code> for

     * the <code>Component</code> c,

     * the <code>Component</code> to observe, and the action(s)

     * permitted for this drag operation.

     * @param ds  The DragSource for the Component c

     * @param c   The Component to observe

     * @param act The actions permitted for this drag

     */

    protected MouseDragGestureRecognizer(DragSource ds, Component c, int act) {

        this(ds, c, act, null);

    }

    /**

     * Construct a new <code>MouseDragGestureRecognizer</code>

     * given the <code>DragSource</code> for the

     * <code>Component</code> c, and the

     * <code>Component</code> to observe.

     * @param ds  The DragSource for the Component c

     * @param c   The Component to observe

     */

    protected MouseDragGestureRecognizer(DragSource ds, Component c) {

        this(ds, c, DnDConstants.ACTION_NONE);

    }

    /**

     * Construct a new <code>MouseDragGestureRecognizer</code>

     * given the <code>DragSource</code> for the <code>Component</code>.

     * @param ds  The DragSource for the Component

     */

    protected MouseDragGestureRecognizer(DragSource ds) {

        this(ds, null);

    }

    /**

     * register this DragGestureRecognizer's Listeners with the Component

     */

    protected void registerListeners() {

        component.addMouseListener(this);

        component.addMouseMotionListener(this);

    }

    /**

     * unregister this DragGestureRecognizer's Listeners with the Component

     *

     * subclasses must override this method

     */

    protected void unregisterListeners() {

        component.removeMouseListener(this);

        component.removeMouseMotionListener(this);

    }

    /**

     * Invoked when the mouse has been clicked on a component.

     * @param e the <code>MouseEvent</code>

     */

    public void mouseClicked(MouseEvent e) { }

    /**

     * Invoked when a mouse button has been

     * pressed on a <code>Component</code>.

     * @param e the <code>MouseEvent</code>

     */

    public void mousePressed(MouseEvent e) { }

    /**

     * Invoked when a mouse button has been released on a component.

     * @param e the <code>MouseEvent</code>

     */

    public void mouseReleased(MouseEvent e) { }

    /**

     * Invoked when the mouse enters a component.

     * @param e the <code>MouseEvent</code>

     */

    public void mouseEntered(MouseEvent e) { }

    /**

     * Invoked when the mouse exits a component.

     * @param e the <code>MouseEvent</code>

     */

    public void mouseExited(MouseEvent e) { }

    /**

     * Invoked when a mouse button is pressed on a component.

     * @param e the <code>MouseEvent</code>

     */

    public void mouseDragged(MouseEvent e) { }

    /**

     * Invoked when the mouse button has been moved on a component

     * (with no buttons no down).

     * @param e the <code>MouseEvent</code>

     */

    public void mouseMoved(MouseEvent e) { }

}