001    /* DragGestureEvent.java --
002       Copyright (C) 2002 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package java.awt.dnd;
040    
041    import java.awt.Component;
042    import java.awt.Cursor;
043    import java.awt.Image;
044    import java.awt.Point;
045    import java.awt.datatransfer.Transferable;
046    import java.awt.event.InputEvent;
047    import java.util.EventObject;
048    import java.util.Iterator;
049    import java.util.List;
050    
051    public class DragGestureEvent extends EventObject
052    {
053      /**
054       * Compatible with JDK 1.2+.
055       */
056      private static final long serialVersionUID = 9080172649166731306L;
057    
058      private DragSource dragSource;
059      private Component component;
060      private final Point origin;
061      private final int action;
062      private List<InputEvent> events;
063      private DragGestureRecognizer dgr;
064    
065      /**
066       * Constructs a new DragGestureEvent.
067       * @param dgr - DragGestureRecognizer firing this event
068       * @param action - user's preferred action
069       * @param origin - origin of the drag
070       * @param events - List of events that make up the gesture
071       * @throws IllegalArgumentException - if input parameters are null
072       */
073      public DragGestureEvent(DragGestureRecognizer dgr, int action, Point origin,
074                              List<? extends InputEvent> events)
075      {
076        super(dgr);
077        if (origin == null || events == null || dgr == null)
078          throw new IllegalArgumentException();
079    
080        this.origin = origin;
081        this.action = action;
082        this.events = (List<InputEvent>) events;
083        this.dgr = dgr;
084        this.component = dgr.getComponent();
085        this.dragSource = dgr.getDragSource();
086      }
087    
088      /**
089       * Returns the source casted as a DragGestureRecognizer.
090       *
091       * @return the source casted as a DragGestureRecognizer.
092       */
093      public DragGestureRecognizer getSourceAsDragGestureRecognizer()
094      {
095        return (DragGestureRecognizer) getSource();
096      }
097    
098      /**
099       * Returns the Component corresponding to this.
100       *
101       * @return the Component corresponding to this.
102       */
103      public Component getComponent()
104      {
105        return component;
106      }
107    
108      /**
109       * Gets the DragSource corresponding to this.
110       *
111       * @return the DragSource corresponding to this.
112       */
113      public DragSource getDragSource()
114      {
115        return dragSource;
116      }
117    
118      /**
119       * Returns the origin of the drag.
120       *
121       * @return the origin of the drag.
122       */
123      public Point getDragOrigin()
124      {
125        return origin;
126      }
127    
128      /**
129       * Gets an iterator representation of the List of events.
130       *
131       * @return an iterator representation of the List of events.
132       */
133      public Iterator<InputEvent> iterator()
134      {
135        return events.iterator();
136      }
137    
138      /**
139       * Gets an array representation of the List of events.
140       *
141       * @return an array representation of the List of events.
142       */
143      public Object[] toArray()
144      {
145        return events.toArray();
146      }
147    
148      /**
149       * Gets an array representation of the List of events.
150       *
151       * @param array - the array to store the events in.
152       * @return an array representation of the List of events.
153       */
154      public Object[] toArray(Object[] array)
155      {
156        return events.toArray(array);
157      }
158    
159      /**
160       * Gets the user's preferred action.
161       *
162       * @return the user's preferred action.
163       */
164      public int getDragAction()
165      {
166        return action;
167      }
168    
169      /**
170       * Get the event that triggered this gesture.
171       *
172       * @return the event that triggered this gesture.
173       */
174      public InputEvent getTriggerEvent()
175      {
176        return dgr.getTriggerEvent();
177      }
178    
179      /**
180       * Starts the drag given the initial Cursor to display, the Transferable
181       * object, and the DragSourceListener to use.
182       *
183       * @exception InvalidDnDOperationException If the Drag and Drop system is
184       * unable to initiate a drag operation, or if the user attempts to start
185       * a drag while an existing drag operation is still executing.
186       */
187      public void startDrag(Cursor dragCursor, Transferable trans)
188      {
189        startDrag(dragCursor, null, null, trans, null);
190      }
191    
192      /**
193       * Starts the drag given the initial Cursor to display, the Transferable
194       * object, and the DragSourceListener to use.
195       *
196       * @exception InvalidDnDOperationException If the Drag and Drop system is
197       * unable to initiate a drag operation, or if the user attempts to start
198       * a drag while an existing drag operation is still executing.
199       */
200      public void startDrag(Cursor dragCursor, Transferable trans,
201                            DragSourceListener l)
202      {
203        startDrag(dragCursor, null, null, trans, l);
204      }
205    
206      /**
207       * Starts the drag given the initial Cursor to display, the Transferable
208       * object, and the DragSourceListener to use.
209       *
210       * @exception InvalidDnDOperationException If the Drag and Drop system is
211       * unable to initiate a drag operation, or if the user attempts to start
212       * a drag while an existing drag operation is still executing.
213       */
214      public void startDrag(Cursor dragCursor, Image dragImage, Point imageOffset,
215                            Transferable trans, DragSourceListener l)
216      {
217        dragSource.startDrag(this, dragCursor, dragImage, imageOffset, trans, l);
218      }
219    } // class DragGestureEvent