| /* DragSource.java -- |
| Copyright (C) 2002 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.awt.dnd; |
| |
| import gnu.classpath.NotImplementedException; |
| |
| import java.awt.Component; |
| import java.awt.Cursor; |
| import java.awt.GraphicsEnvironment; |
| import java.awt.HeadlessException; |
| import java.awt.Image; |
| import java.awt.Point; |
| import java.awt.Toolkit; |
| import java.awt.datatransfer.FlavorMap; |
| import java.awt.datatransfer.SystemFlavorMap; |
| import java.awt.datatransfer.Transferable; |
| import java.awt.dnd.peer.DragSourceContextPeer; |
| import java.io.Serializable; |
| import java.util.EventListener; |
| |
| /** |
| * @since 1.2 |
| */ |
| public class DragSource implements Serializable |
| { |
| /** |
| * Compatible with JDK 1.2+. |
| */ |
| private static final long serialVersionUID = 6236096958971414066L; |
| |
| public static final Cursor DefaultCopyDrop = null; |
| public static final Cursor DefaultMoveDrop = null; |
| public static final Cursor DefaultLinkDrop = null; |
| public static final Cursor DefaultCopyNoDrop = null; |
| public static final Cursor DefaultMoveNoDrop = null; |
| public static final Cursor DefaultLinkNoDrop = null; |
| |
| private transient FlavorMap flavorMap = SystemFlavorMap.getDefaultFlavorMap (); |
| private transient DragSourceListener dragSourceListener; |
| private transient DragSourceMotionListener dragSourceMotionListener; |
| |
| private static DragSource ds; |
| private DragSourceContextPeer peer; |
| private DragSourceContext context; |
| |
| /** |
| * Initializes the drag source. |
| * |
| * @exception HeadlessException If GraphicsEnvironment.isHeadless() is true. |
| */ |
| public DragSource() |
| { |
| if (GraphicsEnvironment.isHeadless()) |
| { |
| ds = null; |
| throw new HeadlessException(); |
| } |
| } |
| |
| /** |
| * Gets the default drag source. |
| * |
| * @exception HeadlessException If GraphicsEnvironment.isHeadless() is true. |
| */ |
| public static DragSource getDefaultDragSource() |
| { |
| if (GraphicsEnvironment.isHeadless()) |
| { |
| ds = null; |
| throw new HeadlessException(); |
| } |
| |
| if (ds == null) |
| ds = new DragSource(); |
| return ds; |
| } |
| |
| public static boolean isDragImageSupported() |
| throws NotImplementedException |
| { |
| // FIXME: Implement this |
| return false; |
| } |
| |
| /** |
| * Start a drag, given the DragGestureEvent that initiated the drag. |
| * |
| * @exception InvalidDnDOperationException If the Drag and Drop system is |
| * unable to initiate a drag operation, or if the user attempts to start |
| * a drag while an existing drag operation is still executing. |
| */ |
| public void startDrag(DragGestureEvent trigger, Cursor dragCursor, |
| Image dragImage, Point imageOffset, |
| Transferable trans, DragSourceListener dsl, |
| FlavorMap map) |
| { |
| // http://www.javaworld.com/javaworld/jw-03-1999/jw-03-dragndrop.html |
| |
| // This function creates a DragSourceContext object. This object tracks the |
| // state of the operation by listening to a native peer. In this situation, |
| // the DragSource may be obtained from the event or by an instance variable. |
| // This function also creates a new DragSourceContextPeer. |
| |
| // This function sends the same message to the context, which then forwards |
| // it to the peer, passing itself as a parameter. Now, the native system has |
| // access to the Transferable through the context. |
| |
| // FIXME: Add check to determine if dragging. |
| |
| try |
| { |
| flavorMap = map; |
| |
| if (peer == null) |
| peer = Toolkit.getDefaultToolkit().createDragSourceContextPeer(trigger); |
| |
| if (context == null) |
| context = createDragSourceContext(peer, trigger, |
| dragCursor, |
| dragImage, |
| imageOffset, trans, |
| dsl); |
| |
| if (peer == null) |
| throw new InvalidDnDOperationException(); |
| |
| peer.startDrag(context, dragCursor, dragImage, imageOffset); |
| } |
| catch (Exception e) |
| { |
| throw new InvalidDnDOperationException("Drag and Drop system is " |
| + "unable to initiate a drag operation."); |
| } |
| } |
| |
| /** |
| * Start a drag, given the DragGestureEvent that initiated the drag. |
| * |
| * @exception InvalidDnDOperationException If the Drag and Drop system is |
| * unable to initiate a drag operation, or if the user attempts to start |
| * a drag while an existing drag operation is still executing. |
| */ |
| public void startDrag(DragGestureEvent trigger, Cursor dragCursor, |
| Transferable trans, DragSourceListener dsl, |
| FlavorMap map) |
| { |
| startDrag(trigger, dragCursor, null, null, trans, dsl, map); |
| } |
| |
| /** |
| * Start a drag, given the DragGestureEvent that initiated the drag. |
| * |
| * @exception InvalidDnDOperationException If the Drag and Drop system is |
| * unable to initiate a drag operation, or if the user attempts to start |
| * a drag while an existing drag operation is still executing. |
| */ |
| public void startDrag(DragGestureEvent trigger, Cursor dragCursor, |
| Image dragImage, Point imageOffset, |
| Transferable trans, DragSourceListener dsl) |
| { |
| startDrag(trigger, dragCursor, dragImage, imageOffset, trans, dsl, null); |
| } |
| |
| /** |
| * Start a drag, given the DragGestureEvent that initiated the drag. |
| * |
| * @exception InvalidDnDOperationException If the Drag and Drop system is |
| * unable to initiate a drag operation, or if the user attempts to start |
| * a drag while an existing drag operation is still executing. |
| */ |
| public void startDrag(DragGestureEvent trigger, Cursor dragCursor, |
| Transferable trans, DragSourceListener dsl) |
| { |
| startDrag(trigger, dragCursor, null, null, trans, dsl, null); |
| } |
| |
| /** |
| * Creates the DragSourceContext to handle this drag. |
| * |
| * @exception IllegalArgumentException |
| * @exception NullPointerException If dscp, dgl, dragImage or t is null. |
| */ |
| protected DragSourceContext |
| createDragSourceContext(DragSourceContextPeer peer, DragGestureEvent dge, |
| Cursor cursor, Image image, Point offset, |
| Transferable t, DragSourceListener dsl) |
| { |
| return new DragSourceContext(peer, dge, cursor, image, offset, t, dsl); |
| } |
| |
| public FlavorMap getFlavorMap() |
| { |
| return flavorMap; |
| } |
| |
| public DragGestureRecognizer createDragGestureRecognizer(Class recognizer, |
| Component c, |
| int actions, |
| DragGestureListener dgl) |
| { |
| return Toolkit.getDefaultToolkit().createDragGestureRecognizer(recognizer, |
| this, c, |
| actions, dgl); |
| } |
| |
| public DragGestureRecognizer createDefaultDragGestureRecognizer(Component c, |
| int actions, |
| DragGestureListener dgl) |
| { |
| return createDragGestureRecognizer(MouseDragGestureRecognizer.class, c, |
| actions, dgl); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public void addDragSourceListener(DragSourceListener l) |
| { |
| DnDEventMulticaster.add (dragSourceListener, l); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public void removeDragSourceListener(DragSourceListener l) |
| { |
| DnDEventMulticaster.remove (dragSourceListener, l); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public DragSourceListener[] getDragSourceListeners() |
| { |
| return (DragSourceListener[]) getListeners (DragSourceListener.class); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public void addDragSourceMotionListener(DragSourceMotionListener l) |
| { |
| DnDEventMulticaster.add (dragSourceMotionListener, l); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public void removeDragSourceMotionListener(DragSourceMotionListener l) |
| { |
| DnDEventMulticaster.remove (dragSourceMotionListener, l); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public DragSourceMotionListener[] getDragSourceMotionListeners () |
| { |
| return (DragSourceMotionListener[]) getListeners |
| (DragSourceMotionListener.class); |
| } |
| |
| /** |
| * @since 1.4 |
| */ |
| public EventListener[] getListeners (Class listenerType) |
| { |
| if (listenerType == DragSourceListener.class) |
| return DnDEventMulticaster.getListeners (dragSourceListener, |
| listenerType); |
| |
| if (listenerType == DragSourceMotionListener.class) |
| return DnDEventMulticaster.getListeners (dragSourceMotionListener, |
| listenerType); |
| |
| // Return an empty EventListener array. |
| return new EventListener [0]; |
| } |
| |
| /** |
| * TODO |
| * @return |
| * |
| * @since 1.5 |
| */ |
| public static int getDragThreshold() |
| throws NotImplementedException |
| { |
| // FIXME: Not implemented. |
| return 4; |
| } |
| } // class DragSource |