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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.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package java.awt.dnd;
import java.awt.Point;
import java.util.EventObject;
/**
* This class is the base class for
* <code>DragSourceDragEvent</code> and
* <code>DragSourceDropEvent</code>.
* <p>
* <code>DragSourceEvent</code>s are generated whenever the drag enters, moves
* over, or exits a drop site, when the drop action changes, and when the drag
* ends. The location for the generated <code>DragSourceEvent</code> specifies
* the mouse cursor location in screen coordinates at the moment this event
* occured.
* <p>
* In a multi-screen environment without a virtual device, the cursor location is
* specified in the coordinate system of the <i>initiator</i>
* <code>GraphicsConfiguration</code>. The <i>initiator</i>
* <code>GraphicsConfiguration</code> is the <code>GraphicsConfiguration</code>
* of the <code>Component</code> on which the drag gesture for the current drag
* operation was recognized. If the cursor location is outside the bounds of
* the initiator <code>GraphicsConfiguration</code>, the reported coordinates are
* clipped to fit within the bounds of that <code>GraphicsConfiguration</code>.
* <p>
* In a multi-screen environment with a virtual device, the location is specified
* in the corresponding virtual coordinate system. If the cursor location is
* outside the bounds of the virtual device the reported coordinates are
* clipped to fit within the bounds of the virtual device.
*
* @since 1.2
*/
public class DragSourceEvent extends EventObject {
private static final long serialVersionUID = -763287114604032641L;
/**
* The <code>boolean</code> indicating whether the cursor location
* is specified for this event.
*
* @serial
*/
private final boolean locationSpecified;
/**
* The horizontal coordinate for the cursor location at the moment this
* event occured if the cursor location is specified for this event;
* otherwise zero.
*
* @serial
*/
private final int x;
/**
* The vertical coordinate for the cursor location at the moment this event
* occured if the cursor location is specified for this event;
* otherwise zero.
*
* @serial
*/
private final int y;
/**
* Construct a <code>DragSourceEvent</code>
* given a specified <code>DragSourceContext</code>.
* The coordinates for this <code>DragSourceEvent</code>
* are not specified, so <code>getLocation</code> will return
* <code>null</code> for this event.
*
* @param dsc the <code>DragSourceContext</code>
*
* @throws <code>IllegalArgumentException</code> if <code>dsc</code> is <code>null</code>.
*
* @see #getLocation
*/
public DragSourceEvent(DragSourceContext dsc) {
super(dsc);
locationSpecified = false;
this.x = 0;
this.y = 0;
}
/**
* Construct a <code>DragSourceEvent</code> given a specified
* <code>DragSourceContext</code>, and coordinates of the cursor
* location.
*
* @param dsc the <code>DragSourceContext</code>
* @param x the horizontal coordinate for the cursor location
* @param y the vertical coordinate for the cursor location
*
* @throws <code>IllegalArgumentException</code> if <code>dsc</code> is <code>null</code>.
*
* @since 1.4
*/
public DragSourceEvent(DragSourceContext dsc, int x, int y) {
super(dsc);
locationSpecified = true;
this.x = x;
this.y = y;
}
/**
* This method returns the <code>DragSourceContext</code> that
* originated the event.
* <P>
* @return the <code>DragSourceContext</code> that originated the event
*/
public DragSourceContext getDragSourceContext() {
return (DragSourceContext)getSource();
}
/**
* This method returns a <code>Point</code> indicating the cursor
* location in screen coordinates at the moment this event occured, or
* <code>null</code> if the cursor location is not specified for this
* event.
*
* @return the <code>Point</code> indicating the cursor location
* or <code>null</code> if the cursor location is not specified
* @since 1.4
*/
public Point getLocation() {
if (locationSpecified) {
return new Point(x, y);
} else {
return null;
}
}
/**
* This method returns the horizontal coordinate of the cursor location in
* screen coordinates at the moment this event occured, or zero if the
* cursor location is not specified for this event.
*
* @return an integer indicating the horizontal coordinate of the cursor
* location or zero if the cursor location is not specified
* @since 1.4
*/
public int getX() {
return x;
}
/**
* This method returns the vertical coordinate of the cursor location in
* screen coordinates at the moment this event occured, or zero if the
* cursor location is not specified for this event.
*
* @return an integer indicating the vertical coordinate of the cursor
* location or zero if the cursor location is not specified
* @since 1.4
*/
public int getY() {
return y;
}
}