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*
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* 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).
*
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 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}
* defines a {@code DragGestureRecognizer}
* 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}
* given the {@code DragSource} for the
* {@code Component} c, the {@code Component}
* to observe, the action(s)
* permitted for this drag operation, and
* the {@code DragGestureListener} 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}
* given the {@code DragSource} for
* the {@code Component} c,
* the {@code Component} 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}
* given the {@code DragSource} for the
* {@code Component} c, and the
* {@code Component} 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}
* given the {@code DragSource} for the {@code Component}.
*
* @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}
*/
public void mouseClicked(MouseEvent e) { }
/**
* Invoked when a mouse button has been
* pressed on a {@code Component}.
*
* @param e the {@code MouseEvent}
*/
public void mousePressed(MouseEvent e) { }
/**
* Invoked when a mouse button has been released on a component.
*
* @param e the {@code MouseEvent}
*/
public void mouseReleased(MouseEvent e) { }
/**
* Invoked when the mouse enters a component.
*
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