/* TransferHandler.java -- Copyright (C) 2004, 2005, 2006, 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 javax.swing; import java.awt.Toolkit; import java.awt.datatransfer.Clipboard; import java.awt.datatransfer.DataFlavor; import java.awt.datatransfer.Transferable; import java.awt.datatransfer.UnsupportedFlavorException; import java.awt.dnd.DragGestureEvent; import java.awt.dnd.DragGestureListener; import java.awt.dnd.DragGestureRecognizer; import java.awt.dnd.DragSource; import java.awt.dnd.DragSourceContext; import java.awt.dnd.DragSourceDragEvent; import java.awt.dnd.DragSourceDropEvent; import java.awt.dnd.DragSourceEvent; import java.awt.dnd.DragSourceListener; import java.awt.event.ActionEvent; import java.awt.event.InputEvent; import java.awt.event.MouseEvent; import java.beans.BeanInfo; import java.beans.IntrospectionException; import java.beans.Introspector; import java.beans.PropertyDescriptor; import java.io.IOException; import java.io.Serializable; import java.lang.reflect.Method; public class TransferHandler implements Serializable { /** * An implementation of {@link Transferable} that can be used to export * data from a component's property. */ private static class PropertyTransferable implements Transferable { /** * The component from which we export. */ private JComponent component; /** * The property descriptor of the property that we handle. */ private PropertyDescriptor property; /** * Creates a new PropertyTransferable. * * @param c the component from which we export * @param prop the property from which we export */ PropertyTransferable(JComponent c, PropertyDescriptor prop) { component = c; property = prop; } /** * Returns the data flavors supported by the Transferable. * * @return the data flavors supported by the Transferable */ public DataFlavor[] getTransferDataFlavors() { DataFlavor[] flavors; Class propClass = property.getPropertyType(); String mime = DataFlavor.javaJVMLocalObjectMimeType + "; class=" + propClass.getName(); try { DataFlavor flavor = new DataFlavor(mime); flavors = new DataFlavor[]{ flavor }; } catch (ClassNotFoundException ex) { flavors = new DataFlavor[0]; } return flavors; } /** * Returns true when the specified data flavor is supported, * false otherwise. * * @return true when the specified data flavor is supported, * false otherwise */ public boolean isDataFlavorSupported(DataFlavor flavor) { Class propClass = property.getPropertyType(); return flavor.getPrimaryType().equals("application") && flavor.getSubType().equals("x-java-jvm-local-objectref") && propClass.isAssignableFrom(flavor.getRepresentationClass()); } /** * Returns the actual transfer data. * * @param flavor the data flavor * * @return the actual transfer data */ public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException { if (isDataFlavorSupported(flavor)) { Method getter = property.getReadMethod(); Object o; try { o = getter.invoke(component, null); return o; } catch (Exception ex) { throw new IOException("Property read failed: " + property.getName()); } } else throw new UnsupportedFlavorException(flavor); } } static class TransferAction extends AbstractAction { private String command; public TransferAction(String command) { super(command); this.command = command; } public void actionPerformed(ActionEvent event) { JComponent component = (JComponent) event.getSource(); TransferHandler transferHandler = component.getTransferHandler(); Clipboard clipboard = getClipboard(component); if (clipboard == null) { // Access denied! Toolkit.getDefaultToolkit().beep(); return; } if (command.equals(COMMAND_COPY)) transferHandler.exportToClipboard(component, clipboard, COPY); else if (command.equals(COMMAND_CUT)) transferHandler.exportToClipboard(component, clipboard, MOVE); else if (command.equals(COMMAND_PASTE)) { Transferable transferable = clipboard.getContents(null); if (transferable != null) transferHandler.importData(component, transferable); } } /** * Get the system cliboard or null if the caller isn't allowed to * access the system clipboard. * * @param component a component, used to get the toolkit. * @return the clipboard */ private static Clipboard getClipboard(JComponent component) { try { return component.getToolkit().getSystemClipboard(); } catch (SecurityException se) { return null; } } } private static class SwingDragGestureRecognizer extends DragGestureRecognizer { protected SwingDragGestureRecognizer(DragGestureListener dgl) { super(DragSource.getDefaultDragSource(), null, NONE, dgl); } void gesture(JComponent c, MouseEvent e, int src, int drag) { setComponent(c); setSourceActions(src); appendEvent(e); fireDragGestureRecognized(drag, e.getPoint()); } protected void registerListeners() { // Nothing to do here. } protected void unregisterListeners() { // Nothing to do here. } } private static class SwingDragHandler implements DragGestureListener, DragSourceListener { private boolean autoscrolls; public void dragGestureRecognized(DragGestureEvent e) { JComponent c = (JComponent) e.getComponent(); TransferHandler th = c.getTransferHandler(); Transferable t = th.createTransferable(c); if (t != null) { autoscrolls = c.getAutoscrolls(); c.setAutoscrolls(false); try { e.startDrag(null, t, this); return; } finally { c.setAutoscrolls(autoscrolls); } } th.exportDone(c, t, NONE); } public void dragDropEnd(DragSourceDropEvent e) { DragSourceContext ctx = e.getDragSourceContext(); JComponent c = (JComponent) ctx.getComponent(); TransferHandler th = c.getTransferHandler(); if (e.getDropSuccess()) { th.exportDone(c, ctx.getTransferable(), e.getDropAction()); } else { th.exportDone(c, ctx.getTransferable(), e.getDropAction()); } c.setAutoscrolls(autoscrolls); } public void dragEnter(DragSourceDragEvent e) { // Nothing to do here. } public void dragExit(DragSourceEvent e) { // Nothing to do here. } public void dragOver(DragSourceDragEvent e) { // Nothing to do here. } public void dropActionChanged(DragSourceDragEvent e) { // Nothing to do here. } } private static final long serialVersionUID = -967749805571669910L; private static final String COMMAND_COPY = "copy"; private static final String COMMAND_CUT = "cut"; private static final String COMMAND_PASTE = "paste"; public static final int NONE = 0; public static final int COPY = 1; public static final int MOVE = 2; public static final int COPY_OR_MOVE = 3; private static Action copyAction = new TransferAction(COMMAND_COPY); private static Action cutAction = new TransferAction(COMMAND_CUT); private static Action pasteAction = new TransferAction(COMMAND_PASTE); private int sourceActions; private Icon visualRepresentation; /** * The name of the property into/from which this TransferHandler * imports/exports. */ private String propertyName; /** * The DragGestureRecognizer for Swing. */ private SwingDragGestureRecognizer recognizer; public static Action getCopyAction() { return copyAction; } public static Action getCutAction() { return cutAction; } public static Action getPasteAction() { return pasteAction; } protected TransferHandler() { this.sourceActions = NONE; } public TransferHandler(String property) { propertyName = property; this.sourceActions = property != null ? COPY : NONE; } /** * Returns true if the data in this TransferHandler can be * imported into the specified component. This will be the case when: *