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	/*
	* Copyright (c) 1998, 2003, 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 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.
	* <P>
	* @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.
	* <P>
	* @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.
	* <P>
	* @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>.
	* <P>
	* @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.
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mouseClicked(MouseEvent e) { }

	/**
	* Invoked when a mouse button has been
	* pressed on a <code>Component</code>.
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mousePressed(MouseEvent e) { }

	/**
	* Invoked when a mouse button has been released on a component.
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mouseReleased(MouseEvent e) { }

	/**
	* Invoked when the mouse enters a component.
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mouseEntered(MouseEvent e) { }

	/**
	* Invoked when the mouse exits a component.
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mouseExited(MouseEvent e) { }

	/**
	* Invoked when a mouse button is pressed on a component.
	* <P>
	* @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).
	* <P>
	* @param e the <code>MouseEvent</code>
	*/

	public void mouseMoved(MouseEvent e) { }
	}

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