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	/*
	* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing;

	import java.awt.*;
	import java.awt.event.*;
	import java.awt.datatransfer.*;
	import java.awt.dnd.*;
	import java.beans.*;
	import java.lang.reflect.*;
	import java.io.*;
	import java.util.TooManyListenersException;
	import javax.swing.plaf.UIResource;
	import javax.swing.event.*;
	import javax.swing.text.JTextComponent;

	import sun.reflect.misc.MethodUtil;
	import sun.swing.SwingUtilities2;
	import sun.awt.AppContext;
	import sun.swing.*;
	import sun.awt.SunToolkit;

	import java.security.AccessController;
	import java.security.PrivilegedAction;

	import java.security.AccessControlContext;
	import java.security.ProtectionDomain;
	import sun.misc.SharedSecrets;
	import sun.misc.JavaSecurityAccess;

	import sun.awt.AWTAccessor;

	/**
	* This class is used to handle the transfer of a <code>Transferable</code>
	* to and from Swing components. The <code>Transferable</code> is used to
	* represent data that is exchanged via a cut, copy, or paste
	* to/from a clipboard. It is also used in drag-and-drop operations
	* to represent a drag from a component, and a drop to a component.
	* Swing provides functionality that automatically supports cut, copy,
	* and paste keyboard bindings that use the functionality provided by
	* an implementation of this class. Swing also provides functionality
	* that automatically supports drag and drop that uses the functionality
	* provided by an implementation of this class. The Swing developer can
	* concentrate on specifying the semantics of a transfer primarily by setting
	* the <code>transferHandler</code> property on a Swing component.
	* <p>
	* This class is implemented to provide a default behavior of transferring
	* a component property simply by specifying the name of the property in
	* the constructor. For example, to transfer the foreground color from
	* one component to another either via the clipboard or a drag and drop operation
	* a <code>TransferHandler</code> can be constructed with the string "foreground". The
	* built in support will use the color returned by <code>getForeground</code> as the source
	* of the transfer, and <code>setForeground</code> for the target of a transfer.
	* <p>
	* Please see
	* <a href="https://docs.oracle.com/javase/tutorial/uiswing/dnd/index.html">
	* How to Use Drag and Drop and Data Transfer</a>,
	* a section in <em>The Java Tutorial</em>, for more information.
	*
	*
	* @author Timothy Prinzing
	* @author Shannon Hickey
	* @since 1.4
	*/
	@SuppressWarnings("serial")
	public class TransferHandler implements Serializable {

	/**
	* An <code>int</code> representing no transfer action.
	*/
	public static final int NONE = DnDConstants.ACTION_NONE;

	/**
	* An <code>int</code> representing a "copy" transfer action.
	* This value is used when data is copied to a clipboard
	* or copied elsewhere in a drag and drop operation.
	*/
	public static final int COPY = DnDConstants.ACTION_COPY;

	/**
	* An <code>int</code> representing a "move" transfer action.
	* This value is used when data is moved to a clipboard (i.e. a cut)
	* or moved elsewhere in a drag and drop operation.
	*/
	public static final int MOVE = DnDConstants.ACTION_MOVE;

	/**
	* An <code>int</code> representing a source action capability of either
	* "copy" or "move".
	*/
	public static final int COPY_OR_MOVE = DnDConstants.ACTION_COPY_OR_MOVE;

	/**
	* An <code>int</code> representing a "link" transfer action.
	* This value is used to specify that data should be linked in a drag
	* and drop operation.
	*
	* @see java.awt.dnd.DnDConstants#ACTION_LINK
	* @since 1.6
	*/
	public static final int LINK = DnDConstants.ACTION_LINK;

	/**
	* An interface to tag things with a {@code getTransferHandler} method.
	*/
	interface HasGetTransferHandler {

	/** Returns the {@code TransferHandler}.
	*
	* @return The {@code TransferHandler} or {@code null}
	*/
	public TransferHandler getTransferHandler();
	}

	/**
	* Represents a location where dropped data should be inserted.
	* This is a base class that only encapsulates a point.
	* Components supporting drop may provide subclasses of this
	* containing more information.
	* <p>
	* Developers typically shouldn't create instances of, or extend, this
	* class. Instead, these are something provided by the DnD
	* implementation by <code>TransferSupport</code> instances and by
	* components with a <code>getDropLocation()</code> method.
	*
	* @see javax.swing.TransferHandler.TransferSupport#getDropLocation
	* @since 1.6
	*/
	public static class DropLocation {
	private final Point dropPoint;

	/**
	* Constructs a drop location for the given point.
	*
	* @param dropPoint the drop point, representing the mouse's
	* current location within the component.
	* @throws IllegalArgumentException if the point
	* is <code>null</code>
	*/
	protected DropLocation(Point dropPoint) {
	if (dropPoint == null) {
	throw new IllegalArgumentException("Point cannot be null");
	}

	this.dropPoint = new Point(dropPoint);
	}

	/**
	* Returns the drop point, representing the mouse's
	* current location within the component.
	*
	* @return the drop point.
	*/
	public final Point getDropPoint() {
	return new Point(dropPoint);
	}

	/**
	* Returns a string representation of this drop location.
	* This method is intended to be used for debugging purposes,
	* and the content and format of the returned string may vary
	* between implementations.
	*
	* @return a string representation of this drop location
	*/
	public String toString() {
	return getClass().getName() + "[dropPoint=" + dropPoint + "]";
	}
	};

	/**
	* This class encapsulates all relevant details of a clipboard
	* or drag and drop transfer, and also allows for customizing
	* aspects of the drag and drop experience.
	* <p>
	* The main purpose of this class is to provide the information
	* needed by a developer to determine the suitability of a
	* transfer or to import the data contained within. But it also
	* doubles as a controller for customizing properties during drag
	* and drop, such as whether or not to show the drop location,
	* and which drop action to use.
	* <p>
	* Developers typically need not create instances of this
	* class. Instead, they are something provided by the DnD
	* implementation to certain methods in <code>TransferHandler</code>.
	*
	* @see #canImport(TransferHandler.TransferSupport)
	* @see #importData(TransferHandler.TransferSupport)
	* @since 1.6
	*/
	public final static class TransferSupport {
	private boolean isDrop;
	private Component component;

	private boolean showDropLocationIsSet;
	private boolean showDropLocation;

	private int dropAction = -1;

	/**
	* The source is a {@code DropTargetDragEvent} or
	* {@code DropTargetDropEvent} for drops,
	* and a {@code Transferable} otherwise
	*/
	private Object source;

	private DropLocation dropLocation;

	/**
	* Create a <code>TransferSupport</code> with <code>isDrop()</code>
	* <code>true</code> for the given component, event, and index.
	*
	* @param component the target component
	* @param event a <code>DropTargetEvent</code>
	*/
	private TransferSupport(Component component,
	DropTargetEvent event) {

	isDrop = true;
	setDNDVariables(component, event);
	}

	/**
	* Create a <code>TransferSupport</code> with <code>isDrop()</code>
	* <code>false</code> for the given component and
	* <code>Transferable</code>.
	*
	* @param component the target component
	* @param transferable the transferable
	* @throws NullPointerException if either parameter
	* is <code>null</code>
	*/
	public TransferSupport(Component component, Transferable transferable) {
	if (component == null) {
	throw new NullPointerException("component is null");
	}

	if (transferable == null) {
	throw new NullPointerException("transferable is null");
	}

	isDrop = false;
	this.component = component;
	this.source = transferable;
	}

	/**
	* Allows for a single instance to be reused during DnD.
	*
	* @param component the target component
	* @param event a <code>DropTargetEvent</code>
	*/
	private void setDNDVariables(Component component,
	DropTargetEvent event) {

	assert isDrop;

	this.component = component;
	this.source = event;
	dropLocation = null;
	dropAction = -1;
	showDropLocationIsSet = false;

	if (source == null) {
	return;
	}

	assert source instanceof DropTargetDragEvent \|\|
	source instanceof DropTargetDropEvent;

	Point p = source instanceof DropTargetDragEvent
	? ((DropTargetDragEvent)source).getLocation()
	: ((DropTargetDropEvent)source).getLocation();

	if (SunToolkit.isInstanceOf(component, "javax.swing.text.JTextComponent")) {
	dropLocation = SwingAccessor.getJTextComponentAccessor().
	dropLocationForPoint((JTextComponent)component, p);
	} else if (component instanceof JComponent) {
	dropLocation = ((JComponent)component).dropLocationForPoint(p);
	}

	/*
	* The drop location may be null at this point if the component
	* doesn't return custom drop locations. In this case, a point-only
	* drop location will be created lazily when requested.
	*/
	}

	/**
	* Returns whether or not this <code>TransferSupport</code>
	* represents a drop operation.
	*
	* @return <code>true</code> if this is a drop operation,
	* <code>false</code> otherwise.
	*/
	public boolean isDrop() {
	return isDrop;
	}

	/**
	* Returns the target component of this transfer.
	*
	* @return the target component
	*/
	public Component getComponent() {
	return component;
	}

	/**
	* Checks that this is a drop and throws an
	* {@code IllegalStateException} if it isn't.
	*
	* @throws IllegalStateException if {@code isDrop} is false.
	*/
	private void assureIsDrop() {
	if (!isDrop) {
	throw new IllegalStateException("Not a drop");
	}
	}

	/**
	* Returns the current (non-{@code null}) drop location for the component,
	* when this {@code TransferSupport} represents a drop.
	* <p>
	* Note: For components with built-in drop support, this location
	* will be a subclass of {@code DropLocation} of the same type
	* returned by that component's {@code getDropLocation} method.
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @return the drop location
	* @throws IllegalStateException if this is not a drop
	* @see #isDrop()
	*/
	public DropLocation getDropLocation() {
	assureIsDrop();

	if (dropLocation == null) {
	/*
	* component didn't give us a custom drop location,
	* so lazily create a point-only location
	*/
	Point p = source instanceof DropTargetDragEvent
	? ((DropTargetDragEvent)source).getLocation()
	: ((DropTargetDropEvent)source).getLocation();

	dropLocation = new DropLocation(p);
	}

	return dropLocation;
	}

	/**
	* Sets whether or not the drop location should be visually indicated
	* for the transfer - which must represent a drop. This is applicable to
	* those components that automatically
	* show the drop location when appropriate during a drag and drop
	* operation). By default, the drop location is shown only when the
	* {@code TransferHandler} has said it can accept the import represented
	* by this {@code TransferSupport}. With this method you can force the
	* drop location to always be shown, or always not be shown.
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @param showDropLocation whether or not to indicate the drop location
	* @throws IllegalStateException if this is not a drop
	* @see #isDrop()
	*/
	public void setShowDropLocation(boolean showDropLocation) {
	assureIsDrop();

	this.showDropLocation = showDropLocation;
	this.showDropLocationIsSet = true;
	}

	/**
	* Sets the drop action for the transfer - which must represent a drop
	* - to the given action,
	* instead of the default user drop action. The action must be
	* supported by the source's drop actions, and must be one
	* of {@code COPY}, {@code MOVE} or {@code LINK}.
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @param dropAction the drop action
	* @throws IllegalStateException if this is not a drop
	* @throws IllegalArgumentException if an invalid action is specified
	* @see #getDropAction
	* @see #getUserDropAction
	* @see #getSourceDropActions
	* @see #isDrop()
	*/
	public void setDropAction(int dropAction) {
	assureIsDrop();

	int action = dropAction & getSourceDropActions();

	if (!(action == COPY \|\| action == MOVE \|\| action == LINK)) {
	throw new IllegalArgumentException("unsupported drop action: " + dropAction);
	}

	this.dropAction = dropAction;
	}

	/**
	* Returns the action chosen for the drop, when this
	* {@code TransferSupport} represents a drop.
	* <p>
	* Unless explicitly chosen by way of {@code setDropAction},
	* this returns the user drop action provided by
	* {@code getUserDropAction}.
	* <p>
	* You may wish to query this in {@code TransferHandler}'s
	* {@code importData} method to customize processing based
	* on the action.
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @return the action chosen for the drop
	* @throws IllegalStateException if this is not a drop
	* @see #setDropAction
	* @see #getUserDropAction
	* @see #isDrop()
	*/
	public int getDropAction() {
	return dropAction == -1 ? getUserDropAction() : dropAction;
	}

	/**
	* Returns the user drop action for the drop, when this
	* {@code TransferSupport} represents a drop.
	* <p>
	* The user drop action is chosen for a drop as described in the
	* documentation for {@link java.awt.dnd.DropTargetDragEvent} and
	* {@link java.awt.dnd.DropTargetDropEvent}. A different action
	* may be chosen as the drop action by way of the {@code setDropAction}
	* method.
	* <p>
	* You may wish to query this in {@code TransferHandler}'s
	* {@code canImport} method when determining the suitability of a
	* drop or when deciding on a drop action to explicitly choose.
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @return the user drop action
	* @throws IllegalStateException if this is not a drop
	* @see #setDropAction
	* @see #getDropAction
	* @see #isDrop()
	*/
	public int getUserDropAction() {
	assureIsDrop();

	return (source instanceof DropTargetDragEvent)
	? ((DropTargetDragEvent)source).getDropAction()
	: ((DropTargetDropEvent)source).getDropAction();
	}

	/**
	* Returns the drag source's supported drop actions, when this
	* {@code TransferSupport} represents a drop.
	* <p>
	* The source actions represent the set of actions supported by the
	* source of this transfer, and are represented as some bitwise-OR
	* combination of {@code COPY}, {@code MOVE} and {@code LINK}.
	* You may wish to query this in {@code TransferHandler}'s
	* {@code canImport} method when determining the suitability of a drop
	* or when deciding on a drop action to explicitly choose. To determine
	* if a particular action is supported by the source, bitwise-AND
	* the action with the source drop actions, and then compare the result
	* against the original action. For example:
	* <pre>
	* boolean copySupported = (COPY & getSourceDropActions()) == COPY;
	* </pre>
	* <p>
	* This method is only for use with drag and drop transfers.
	* Calling it when {@code isDrop()} is {@code false} results
	* in an {@code IllegalStateException}.
	*
	* @return the drag source's supported drop actions
	* @throws IllegalStateException if this is not a drop
	* @see #isDrop()
	*/
	public int getSourceDropActions() {
	assureIsDrop();

	return (source instanceof DropTargetDragEvent)
	? ((DropTargetDragEvent)source).getSourceActions()
	: ((DropTargetDropEvent)source).getSourceActions();
	}

	/**
	* Returns the data flavors for this transfer.
	*
	* @return the data flavors for this transfer
	*/
	public DataFlavor[] getDataFlavors() {
	if (isDrop) {
	if (source instanceof DropTargetDragEvent) {
	return ((DropTargetDragEvent)source).getCurrentDataFlavors();
	} else {
	return ((DropTargetDropEvent)source).getCurrentDataFlavors();
	}
	}

	return ((Transferable)source).getTransferDataFlavors();
	}

	/**
	* Returns whether or not the given data flavor is supported.
	*
	* @param df the <code>DataFlavor</code> to test
	* @return whether or not the given flavor is supported.
	*/
	public boolean isDataFlavorSupported(DataFlavor df) {
	if (isDrop) {
	if (source instanceof DropTargetDragEvent) {
	return ((DropTargetDragEvent)source).isDataFlavorSupported(df);
	} else {
	return ((DropTargetDropEvent)source).isDataFlavorSupported(df);
	}
	}

	return ((Transferable)source).isDataFlavorSupported(df);
	}

	/**
	* Returns the <code>Transferable</code> associated with this transfer.
	* <p>
	* Note: Unless it is necessary to fetch the <code>Transferable</code>
	* directly, use one of the other methods on this class to inquire about
	* the transfer. This may perform better than fetching the
	* <code>Transferable</code> and asking it directly.
	*
	* @return the <code>Transferable</code> associated with this transfer
	*/
	public Transferable getTransferable() {
	if (isDrop) {
	if (source instanceof DropTargetDragEvent) {
	return ((DropTargetDragEvent)source).getTransferable();
	} else {
	return ((DropTargetDropEvent)source).getTransferable();
	}
	}

	return (Transferable)source;
	}
	}


	/**
	* Returns an {@code Action} that performs cut operations to the
	* clipboard. When performed, this action operates on the {@code JComponent}
	* source of the {@code ActionEvent} by invoking {@code exportToClipboard},
	* with a {@code MOVE} action, on the component's {@code TransferHandler}.
	*
	* @return an {@code Action} for performing cuts to the clipboard
	*/
	public static Action getCutAction() {
	return cutAction;
	}

	/**
	* Returns an {@code Action} that performs copy operations to the
	* clipboard. When performed, this action operates on the {@code JComponent}
	* source of the {@code ActionEvent} by invoking {@code exportToClipboard},
	* with a {@code COPY} action, on the component's {@code TransferHandler}.
	*
	* @return an {@code Action} for performing copies to the clipboard
	*/
	public static Action getCopyAction() {
	return copyAction;
	}

	/**
	* Returns an {@code Action} that performs paste operations from the
	* clipboard. When performed, this action operates on the {@code JComponent}
	* source of the {@code ActionEvent} by invoking {@code importData},
	* with the clipboard contents, on the component's {@code TransferHandler}.
	*
	* @return an {@code Action} for performing pastes from the clipboard
	*/
	public static Action getPasteAction() {
	return pasteAction;
	}


	/**
	* Constructs a transfer handler that can transfer a Java Bean property
	* from one component to another via the clipboard or a drag and drop
	* operation.
	*
	* @param property the name of the property to transfer; this can
	* be <code>null</code> if there is no property associated with the transfer
	* handler (a subclass that performs some other kind of transfer, for example)
	*/
	public TransferHandler(String property) {
	propertyName = property;
	}

	/**
	* Convenience constructor for subclasses.
	*/
	protected TransferHandler() {
	this(null);
	}


	/**
	* image for the {@code startDrag} method
	*
	* @see java.awt.dnd.DragGestureEvent#startDrag(Cursor dragCursor, Image dragImage, Point imageOffset, Transferable transferable, DragSourceListener dsl)
	*/
	private Image dragImage;

	/**
	* anchor offset for the {@code startDrag} method
	*
	* @see java.awt.dnd.DragGestureEvent#startDrag(Cursor dragCursor, Image dragImage, Point imageOffset, Transferable transferable, DragSourceListener dsl)
	*/
	private Point dragImageOffset;

	/**
	* Sets the drag image parameter. The image has to be prepared
	* for rendering by the moment of the call. The image is stored
	* by reference because of some performance reasons.
	*
	* @param img an image to drag
	*/
	public void setDragImage(Image img) {
	dragImage = img;
	}

	/**
	* Returns the drag image. If there is no image to drag,
	* the returned value is {@code null}.
	*
	* @return the reference to the drag image
	*/
	public Image getDragImage() {
	return dragImage;
	}

	/**
	* Sets an anchor offset for the image to drag.
	* It can not be {@code null}.
	*
	* @param p a {@code Point} object that corresponds
	* to coordinates of an anchor offset of the image
	* relative to the upper left corner of the image
	*/
	public void setDragImageOffset(Point p) {
	dragImageOffset = new Point(p);
	}

	/**
	* Returns an anchor offset for the image to drag.
	*
	* @return a {@code Point} object that corresponds
	* to coordinates of an anchor offset of the image
	* relative to the upper left corner of the image.
	* The point {@code (0,0)} returns by default.
	*/
	public Point getDragImageOffset() {
	if (dragImageOffset == null) {
	return new Point(0,0);
	}
	return new Point(dragImageOffset);
	}

	/**
	* Causes the Swing drag support to be initiated. This is called by
	* the various UI implementations in the <code>javax.swing.plaf.basic</code>
	* package if the dragEnabled property is set on the component.
	* This can be called by custom UI
	* implementations to use the Swing drag support. This method can also be called
	* by a Swing extension written as a subclass of <code>JComponent</code>
	* to take advantage of the Swing drag support.
	* <p>
	* The transfer <em>will not necessarily</em> have been completed at the
	* return of this call (i.e. the call does not block waiting for the drop).
	* The transfer will take place through the Swing implementation of the
	* <code>java.awt.dnd</code> mechanism, requiring no further effort
	* from the developer. The <code>exportDone</code> method will be called
	* when the transfer has completed.
	*
	* @param comp the component holding the data to be transferred;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @param e the event that triggered the transfer
	* @param action the transfer action initially requested;
	* either {@code COPY}, {@code MOVE} or {@code LINK};
	* the DnD system may change the action used during the
	* course of the drag operation
	*/
	public void exportAsDrag(JComponent comp, InputEvent e, int action) {
	int srcActions = getSourceActions(comp);

	// only mouse events supported for drag operations
	if (!(e instanceof MouseEvent)
	// only support known actions
	\|\| !(action == COPY \|\| action == MOVE \|\| action == LINK)
	// only support valid source actions
	\|\| (srcActions & action) == 0) {

	action = NONE;
	}

	if (action != NONE && !GraphicsEnvironment.isHeadless()) {
	if (recognizer == null) {
	recognizer = new SwingDragGestureRecognizer(new DragHandler());
	}
	recognizer.gestured(comp, (MouseEvent)e, srcActions, action);
	} else {
	exportDone(comp, null, NONE);
	}
	}

	/**
	* Causes a transfer from the given component to the
	* given clipboard. This method is called by the default cut and
	* copy actions registered in a component's action map.
	* <p>
	* The transfer will take place using the <code>java.awt.datatransfer</code>
	* mechanism, requiring no further effort from the developer. Any data
	* transfer <em>will</em> be complete and the <code>exportDone</code>
	* method will be called with the action that occurred, before this method
	* returns. Should the clipboard be unavailable when attempting to place
	* data on it, the <code>IllegalStateException</code> thrown by
	* {@link Clipboard#setContents(Transferable, ClipboardOwner)} will
	* be propagated through this method. However,
	* <code>exportDone</code> will first be called with an action
	* of <code>NONE</code> for consistency.
	*
	* @param comp the component holding the data to be transferred;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @param clip the clipboard to transfer the data into
	* @param action the transfer action requested; this should
	* be a value of either <code>COPY</code> or <code>MOVE</code>;
	* the operation performed is the intersection of the transfer
	* capabilities given by getSourceActions and the requested action;
	* the intersection may result in an action of <code>NONE</code>
	* if the requested action isn't supported
	* @throws IllegalStateException if the clipboard is currently unavailable
	* @see Clipboard#setContents(Transferable, ClipboardOwner)
	*/
	public void exportToClipboard(JComponent comp, Clipboard clip, int action)
	throws IllegalStateException {

	if ((action == COPY \|\| action == MOVE)
	&& (getSourceActions(comp) & action) != 0) {

	Transferable t = createTransferable(comp);
	if (t != null) {
	try {
	clip.setContents(t, null);
	exportDone(comp, t, action);
	return;
	} catch (IllegalStateException ise) {
	exportDone(comp, t, NONE);
	throw ise;
	}
	}
	}

	exportDone(comp, null, NONE);
	}

	/**
	* Causes a transfer to occur from a clipboard or a drag and
	* drop operation. The <code>Transferable</code> to be
	* imported and the component to transfer to are contained
	* within the <code>TransferSupport</code>.
	* <p>
	* While the drag and drop implementation calls {@code canImport}
	* to determine the suitability of a transfer before calling this
	* method, the implementation of paste does not. As such, it cannot
	* be assumed that the transfer is acceptable upon a call to
	* this method for paste. It is recommended that {@code canImport} be
	* explicitly called to cover this case.
	* <p>
	* Note: The <code>TransferSupport</code> object passed to this method
	* is only valid for the duration of the method call. It is undefined
	* what values it may contain after this method returns.
	*
	* @param support the object containing the details of
	* the transfer, not <code>null</code>.
	* @return true if the data was inserted into the component,
	* false otherwise
	* @throws NullPointerException if <code>support</code> is {@code null}
	* @see #canImport(TransferHandler.TransferSupport)
	* @since 1.6
	*/
	public boolean importData(TransferSupport support) {
	return support.getComponent() instanceof JComponent
	? importData((JComponent)support.getComponent(), support.getTransferable())
	: false;
	}

	/**
	* Causes a transfer to a component from a clipboard or a
	* DND drop operation. The <code>Transferable</code> represents
	* the data to be imported into the component.
	* <p>
	* Note: Swing now calls the newer version of <code>importData</code>
	* that takes a <code>TransferSupport</code>, which in turn calls this
	* method (if the component in the {@code TransferSupport} is a
	* {@code JComponent}). Developers are encouraged to call and override the
	* newer version as it provides more information (and is the only
	* version that supports use with a {@code TransferHandler} set directly
	* on a {@code JFrame} or other non-{@code JComponent}).
	*
	* @param comp the component to receive the transfer;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @param t the data to import
	* @return true if the data was inserted into the component, false otherwise
	* @see #importData(TransferHandler.TransferSupport)
	*/
	public boolean importData(JComponent comp, Transferable t) {
	PropertyDescriptor prop = getPropertyDescriptor(comp);
	if (prop != null) {
	Method writer = prop.getWriteMethod();
	if (writer == null) {
	// read-only property. ignore
	return false;
	}
	Class<?>[] params = writer.getParameterTypes();
	if (params.length != 1) {
	// zero or more than one argument, ignore
	return false;
	}
	DataFlavor flavor = getPropertyDataFlavor(params[0], t.getTransferDataFlavors());
	if (flavor != null) {
	try {
	Object value = t.getTransferData(flavor);
	Object[] args = { value };
	MethodUtil.invoke(writer, comp, args);
	return true;
	} catch (Exception ex) {
	System.err.println("Invocation failed");
	// invocation code
	}
	}
	}
	return false;
	}

	/**
	* This method is called repeatedly during a drag and drop operation
	* to allow the developer to configure properties of, and to return
	* the acceptability of transfers; with a return value of {@code true}
	* indicating that the transfer represented by the given
	* {@code TransferSupport} (which contains all of the details of the
	* transfer) is acceptable at the current time, and a value of {@code false}
	* rejecting the transfer.
	* <p>
	* For those components that automatically display a drop location during
	* drag and drop, accepting the transfer, by default, tells them to show
	* the drop location. This can be changed by calling
	* {@code setShowDropLocation} on the {@code TransferSupport}.
	* <p>
	* By default, when the transfer is accepted, the chosen drop action is that
	* picked by the user via their drag gesture. The developer can override
	* this and choose a different action, from the supported source
	* actions, by calling {@code setDropAction} on the {@code TransferSupport}.
	* <p>
	* On every call to {@code canImport}, the {@code TransferSupport} contains
	* fresh state. As such, any properties set on it must be set on every
	* call. Upon a drop, {@code canImport} is called one final time before
	* calling into {@code importData}. Any state set on the
	* {@code TransferSupport} during that last call will be available in
	* {@code importData}.
	* <p>
	* This method is not called internally in response to paste operations.
	* As such, it is recommended that implementations of {@code importData}
	* explicitly call this method for such cases and that this method
	* be prepared to return the suitability of paste operations as well.
	* <p>
	* Note: The <code>TransferSupport</code> object passed to this method
	* is only valid for the duration of the method call. It is undefined
	* what values it may contain after this method returns.
	*
	* @param support the object containing the details of
	* the transfer, not <code>null</code>.
	* @return <code>true</code> if the import can happen,
	* <code>false</code> otherwise
	* @throws NullPointerException if <code>support</code> is {@code null}
	* @see #importData(TransferHandler.TransferSupport)
	* @see javax.swing.TransferHandler.TransferSupport#setShowDropLocation
	* @see javax.swing.TransferHandler.TransferSupport#setDropAction
	* @since 1.6
	*/
	public boolean canImport(TransferSupport support) {
	return support.getComponent() instanceof JComponent
	? canImport((JComponent)support.getComponent(), support.getDataFlavors())
	: false;
	}

	/**
	* Indicates whether a component will accept an import of the given
	* set of data flavors prior to actually attempting to import it.
	* <p>
	* Note: Swing now calls the newer version of <code>canImport</code>
	* that takes a <code>TransferSupport</code>, which in turn calls this
	* method (only if the component in the {@code TransferSupport} is a
	* {@code JComponent}). Developers are encouraged to call and override the
	* newer version as it provides more information (and is the only
	* version that supports use with a {@code TransferHandler} set directly
	* on a {@code JFrame} or other non-{@code JComponent}).
	*
	* @param comp the component to receive the transfer;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @param transferFlavors the data formats available
	* @return true if the data can be inserted into the component, false otherwise
	* @see #canImport(TransferHandler.TransferSupport)
	*/
	public boolean canImport(JComponent comp, DataFlavor[] transferFlavors) {
	PropertyDescriptor prop = getPropertyDescriptor(comp);
	if (prop != null) {
	Method writer = prop.getWriteMethod();
	if (writer == null) {
	// read-only property. ignore
	return false;
	}
	Class<?>[] params = writer.getParameterTypes();
	if (params.length != 1) {
	// zero or more than one argument, ignore
	return false;
	}
	DataFlavor flavor = getPropertyDataFlavor(params[0], transferFlavors);
	if (flavor != null) {
	return true;
	}
	}
	return false;
	}

	/**
	* Returns the type of transfer actions supported by the source;
	* any bitwise-OR combination of {@code COPY}, {@code MOVE}
	* and {@code LINK}.
	* <p>
	* Some models are not mutable, so a transfer operation of {@code MOVE}
	* should not be advertised in that case. Returning {@code NONE}
	* disables transfers from the component.
	*
	* @param c the component holding the data to be transferred;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @return {@code COPY} if the transfer property can be found,
	* otherwise returns <code>NONE</code>
	*/
	public int getSourceActions(JComponent c) {
	PropertyDescriptor prop = getPropertyDescriptor(c);
	if (prop != null) {
	return COPY;
	}
	return NONE;
	}

	/**
	* Returns an object that establishes the look of a transfer. This is
	* useful for both providing feedback while performing a drag operation and for
	* representing the transfer in a clipboard implementation that has a visual
	* appearance. The implementation of the <code>Icon</code> interface should
	* not alter the graphics clip or alpha level.
	* The icon implementation need not be rectangular or paint all of the
	* bounding rectangle and logic that calls the icons paint method should
	* not assume the all bits are painted. <code>null</code> is a valid return value
	* for this method and indicates there is no visual representation provided.
	* In that case, the calling logic is free to represent the
	* transferable however it wants.
	* <p>
	* The default Swing logic will not do an alpha blended drag animation if
	* the return is <code>null</code>.
	*
	* @param t the data to be transferred; this value is expected to have been
	* created by the <code>createTransferable</code> method
	* @return <code>null</code>, indicating
	* there is no default visual representation
	*/
	public Icon getVisualRepresentation(Transferable t) {
	return null;
	}

	/**
	* Creates a <code>Transferable</code> to use as the source for
	* a data transfer. Returns the representation of the data to
	* be transferred, or <code>null</code> if the component's
	* property is <code>null</code>
	*
	* @param c the component holding the data to be transferred;
	* provided to enable sharing of <code>TransferHandler</code>s
	* @return the representation of the data to be transferred, or
	* <code>null</code> if the property associated with <code>c</code>
	* is <code>null</code>
	*
	*/
	protected Transferable createTransferable(JComponent c) {
	PropertyDescriptor property = getPropertyDescriptor(c);
	if (property != null) {
	return new PropertyTransferable(property, c);
	}
	return null;
	}

	/**
	* Invoked after data has been exported. This method should remove
	* the data that was transferred if the action was <code>MOVE</code>.
	* <p>
	* This method is implemented to do nothing since <code>MOVE</code>
	* is not a supported action of this implementation
	* (<code>getSourceActions</code> does not include <code>MOVE</code>).
	*
	* @param source the component that was the source of the data
	* @param data The data that was transferred or possibly null
	* if the action is <code>NONE</code>.
	* @param action the actual action that was performed
	*/
	protected void exportDone(JComponent source, Transferable data, int action) {
	}

	/**
	* Fetches the property descriptor for the property assigned to this transfer
	* handler on the given component (transfer handler may be shared). This
	* returns <code>null</code> if the property descriptor can't be found
	* or there is an error attempting to fetch the property descriptor.
	*/
	private PropertyDescriptor getPropertyDescriptor(JComponent comp) {
	if (propertyName == null) {
	return null;
	}
	Class<?> k = comp.getClass();
	BeanInfo bi;
	try {
	bi = Introspector.getBeanInfo(k);
	} catch (IntrospectionException ex) {
	return null;
	}
	PropertyDescriptor props[] = bi.getPropertyDescriptors();
	for (int i=0; i < props.length; i++) {
	if (propertyName.equals(props[i].getName())) {
	Method reader = props[i].getReadMethod();

	if (reader != null) {
	Class<?>[] params = reader.getParameterTypes();

	if (params == null \|\| params.length == 0) {
	// found the desired descriptor
	return props[i];
	}
	}
	}
	}
	return null;
	}

	/**
	* Fetches the data flavor from the array of possible flavors that
	* has data of the type represented by property type. Null is
	* returned if there is no match.
	*/
	private DataFlavor getPropertyDataFlavor(Class<?> k, DataFlavor[] flavors) {
	for(int i = 0; i < flavors.length; i++) {
	DataFlavor flavor = flavors[i];
	if ("application".equals(flavor.getPrimaryType()) &&
	"x-java-jvm-local-objectref".equals(flavor.getSubType()) &&
	k.isAssignableFrom(flavor.getRepresentationClass())) {

	return flavor;
	}
	}
	return null;
	}


	private String propertyName;
	private static SwingDragGestureRecognizer recognizer = null;

	private static DropTargetListener getDropTargetListener() {
	synchronized(DropHandler.class) {
	DropHandler handler =
	(DropHandler)AppContext.getAppContext().get(DropHandler.class);

	if (handler == null) {
	handler = new DropHandler();
	AppContext.getAppContext().put(DropHandler.class, handler);
	}

	return handler;
	}
	}

	static class PropertyTransferable implements Transferable {

	PropertyTransferable(PropertyDescriptor p, JComponent c) {
	property = p;
	component = c;
	}

	// --- Transferable methods ----------------------------------------------

	/**
	* Returns an array of <code>DataFlavor</code> objects indicating the flavors the data
	* can be provided in. The array should be ordered according to preference
	* for providing the data (from most richly descriptive to least descriptive).
	* @return an array of data flavors in which this data can be transferred
	*/
	public DataFlavor[] getTransferDataFlavors() {
	DataFlavor[] flavors = new DataFlavor[1];
	Class<?> propertyType = property.getPropertyType();
	String mimeType = DataFlavor.javaJVMLocalObjectMimeType + ";class=" + propertyType.getName();
	try {
	flavors[0] = new DataFlavor(mimeType);
	} catch (ClassNotFoundException cnfe) {
	flavors = new DataFlavor[0];
	}
	return flavors;
	}

	/**
	* Returns whether the specified data flavor is supported for
	* this object.
	* @param flavor the requested flavor for the data
	* @return true if this <code>DataFlavor</code> is supported,
	* otherwise false
	*/
	public boolean isDataFlavorSupported(DataFlavor flavor) {
	Class<?> propertyType = property.getPropertyType();
	if ("application".equals(flavor.getPrimaryType()) &&
	"x-java-jvm-local-objectref".equals(flavor.getSubType()) &&
	flavor.getRepresentationClass().isAssignableFrom(propertyType)) {

	return true;
	}
	return false;
	}

	/**
	* Returns an object which represents the data to be transferred. The class
	* of the object returned is defined by the representation class of the flavor.
	*
	* @param flavor the requested flavor for the data
	* @see DataFlavor#getRepresentationClass
	* @exception IOException if the data is no longer available
	* in the requested flavor.
	* @exception UnsupportedFlavorException if the requested data flavor is
	* not supported.
	*/
	public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
	if (! isDataFlavorSupported(flavor)) {
	throw new UnsupportedFlavorException(flavor);
	}
	Method reader = property.getReadMethod();
	Object value = null;
	try {
	value = MethodUtil.invoke(reader, component, (Object[])null);
	} catch (Exception ex) {
	throw new IOException("Property read failed: " + property.getName());
	}
	return value;
	}

	JComponent component;
	PropertyDescriptor property;
	}

	/**
	* This is the default drop target for drag and drop operations if
	* one isn't provided by the developer. <code>DropTarget</code>
	* only supports one <code>DropTargetListener</code> and doesn't
	* function properly if it isn't set.
	* This class sets the one listener as the linkage of drop handling
	* to the <code>TransferHandler</code>, and adds support for
	* additional listeners which some of the <code>ComponentUI</code>
	* implementations install to manipulate a drop insertion location.
	*/
	static class SwingDropTarget extends DropTarget implements UIResource {

	SwingDropTarget(Component c) {
	super(c, COPY_OR_MOVE \| LINK, null);
	try {
	// addDropTargetListener is overridden
	// we specifically need to add to the superclass
	super.addDropTargetListener(getDropTargetListener());
	} catch (TooManyListenersException tmle) {}
	}

	public void addDropTargetListener(DropTargetListener dtl) throws TooManyListenersException {
	// Since the super class only supports one DropTargetListener,
	// and we add one from the constructor, we always add to the
	// extended list.
	if (listenerList == null) {
	listenerList = new EventListenerList();
	}
	listenerList.add(DropTargetListener.class, dtl);
	}

	public void removeDropTargetListener(DropTargetListener dtl) {
	if (listenerList != null) {
	listenerList.remove(DropTargetListener.class, dtl);
	}
	}

	// --- DropTargetListener methods (multicast) --------------------------

	public void dragEnter(DropTargetDragEvent e) {
	super.dragEnter(e);
	if (listenerList != null) {
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==DropTargetListener.class) {
	((DropTargetListener)listeners[i+1]).dragEnter(e);
	}
	}
	}
	}

	public void dragOver(DropTargetDragEvent e) {
	super.dragOver(e);
	if (listenerList != null) {
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==DropTargetListener.class) {
	((DropTargetListener)listeners[i+1]).dragOver(e);
	}
	}
	}
	}

	public void dragExit(DropTargetEvent e) {
	super.dragExit(e);
	if (listenerList != null) {
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==DropTargetListener.class) {
	((DropTargetListener)listeners[i+1]).dragExit(e);
	}
	}
	}
	if (!isActive()) {
	// If the Drop target is inactive the dragExit will not be dispatched to the dtListener,
	// so make sure that we clean up the dtListener anyway.
	DropTargetListener dtListener = getDropTargetListener();
	if (dtListener != null && dtListener instanceof DropHandler) {
	((DropHandler)dtListener).cleanup(false);
	}
	}
	}

	public void drop(DropTargetDropEvent e) {
	super.drop(e);
	if (listenerList != null) {
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==DropTargetListener.class) {
	((DropTargetListener)listeners[i+1]).drop(e);
	}
	}
	}
	}

	public void dropActionChanged(DropTargetDragEvent e) {
	super.dropActionChanged(e);
	if (listenerList != null) {
	Object[] listeners = listenerList.getListenerList();
	for (int i = listeners.length-2; i>=0; i-=2) {
	if (listeners[i]==DropTargetListener.class) {
	((DropTargetListener)listeners[i+1]).dropActionChanged(e);
	}
	}
	}
	}

	private EventListenerList listenerList;
	}

	private static class DropHandler implements DropTargetListener,
	Serializable,
	ActionListener {

	private Timer timer;
	private Point lastPosition;
	private Rectangle outer = new Rectangle();
	private Rectangle inner = new Rectangle();
	private int hysteresis = 10;

	private Component component;
	private Object state;
	private TransferSupport support =
	new TransferSupport(null, (DropTargetEvent)null);

	private static final int AUTOSCROLL_INSET = 10;

	/**
	* Update the geometry of the autoscroll region. The geometry is
	* maintained as a pair of rectangles. The region can cause
	* a scroll if the pointer sits inside it for the duration of the
	* timer. The region that causes the timer countdown is the area
	* between the two rectangles.
	* <p>
	* This is implemented to use the visible area of the component
	* as the outer rectangle, and the insets are fixed at 10. Should
	* the component be smaller than a total of 20 in any direction,
	* autoscroll will not occur in that direction.
	*/
	private void updateAutoscrollRegion(JComponent c) {
	// compute the outer
	Rectangle visible = c.getVisibleRect();
	outer.setBounds(visible.x, visible.y, visible.width, visible.height);

	// compute the insets
	Insets i = new Insets(0, 0, 0, 0);
	if (c instanceof Scrollable) {
	int minSize = 2 * AUTOSCROLL_INSET;

	if (visible.width >= minSize) {
	i.left = i.right = AUTOSCROLL_INSET;
	}

	if (visible.height >= minSize) {
	i.top = i.bottom = AUTOSCROLL_INSET;
	}
	}

	// set the inner from the insets
	inner.setBounds(visible.x + i.left,
	visible.y + i.top,
	visible.width - (i.left + i.right),
	visible.height - (i.top + i.bottom));
	}

	/**
	* Perform an autoscroll operation. This is implemented to scroll by the
	* unit increment of the Scrollable using scrollRectToVisible. If the
	* cursor is in a corner of the autoscroll region, more than one axis will
	* scroll.
	*/
	private void autoscroll(JComponent c, Point pos) {
	if (c instanceof Scrollable) {
	Scrollable s = (Scrollable) c;
	if (pos.y < inner.y) {
	// scroll upward
	int dy = s.getScrollableUnitIncrement(outer, SwingConstants.VERTICAL, -1);
	Rectangle r = new Rectangle(inner.x, outer.y - dy, inner.width, dy);
	c.scrollRectToVisible(r);
	} else if (pos.y > (inner.y + inner.height)) {
	// scroll downard
	int dy = s.getScrollableUnitIncrement(outer, SwingConstants.VERTICAL, 1);
	Rectangle r = new Rectangle(inner.x, outer.y + outer.height, inner.width, dy);
	c.scrollRectToVisible(r);
	}

	if (pos.x < inner.x) {
	// scroll left
	int dx = s.getScrollableUnitIncrement(outer, SwingConstants.HORIZONTAL, -1);
	Rectangle r = new Rectangle(outer.x - dx, inner.y, dx, inner.height);
	c.scrollRectToVisible(r);
	} else if (pos.x > (inner.x + inner.width)) {
	// scroll right
	int dx = s.getScrollableUnitIncrement(outer, SwingConstants.HORIZONTAL, 1);
	Rectangle r = new Rectangle(outer.x + outer.width, inner.y, dx, inner.height);
	c.scrollRectToVisible(r);
	}
	}
	}

	/**
	* Initializes the internal properties if they haven't been already
	* inited. This is done lazily to avoid loading of desktop properties.
	*/
	private void initPropertiesIfNecessary() {
	if (timer == null) {
	Toolkit t = Toolkit.getDefaultToolkit();
	Integer prop;

	prop = (Integer)
	t.getDesktopProperty("DnD.Autoscroll.interval");

	timer = new Timer(prop == null ? 100 : prop.intValue(), this);

	prop = (Integer)
	t.getDesktopProperty("DnD.Autoscroll.initialDelay");

	timer.setInitialDelay(prop == null ? 100 : prop.intValue());

	prop = (Integer)
	t.getDesktopProperty("DnD.Autoscroll.cursorHysteresis");

	if (prop != null) {
	hysteresis = prop.intValue();
	}
	}
	}

	/**
	* The timer fired, perform autoscroll if the pointer is within the
	* autoscroll region.
	* <P>
	* @param e the <code>ActionEvent</code>
	*/
	public void actionPerformed(ActionEvent e) {
	updateAutoscrollRegion((JComponent)component);
	if (outer.contains(lastPosition) && !inner.contains(lastPosition)) {
	autoscroll((JComponent)component, lastPosition);
	}
	}

	// --- DropTargetListener methods -----------------------------------

	private void setComponentDropLocation(TransferSupport support,
	boolean forDrop) {

	DropLocation dropLocation = (support == null)
	? null
	: support.getDropLocation();

	if (SunToolkit.isInstanceOf(component, "javax.swing.text.JTextComponent")) {
	state = SwingAccessor.getJTextComponentAccessor().
	setDropLocation((JTextComponent)component, dropLocation, state, forDrop);
	} else if (component instanceof JComponent) {
	state = ((JComponent)component).setDropLocation(dropLocation, state, forDrop);
	}
	}

	private void handleDrag(DropTargetDragEvent e) {
	TransferHandler importer =
	((HasGetTransferHandler)component).getTransferHandler();

	if (importer == null) {
	e.rejectDrag();
	setComponentDropLocation(null, false);
	return;
	}

	support.setDNDVariables(component, e);
	boolean canImport = importer.canImport(support);

	if (canImport) {
	e.acceptDrag(support.getDropAction());
	} else {
	e.rejectDrag();
	}

	boolean showLocation = support.showDropLocationIsSet ?
	support.showDropLocation :
	canImport;

	setComponentDropLocation(showLocation ? support : null, false);
	}

	public void dragEnter(DropTargetDragEvent e) {
	state = null;
	component = e.getDropTargetContext().getComponent();

	handleDrag(e);

	if (component instanceof JComponent) {
	lastPosition = e.getLocation();
	updateAutoscrollRegion((JComponent)component);
	initPropertiesIfNecessary();
	}
	}

	public void dragOver(DropTargetDragEvent e) {
	handleDrag(e);

	if (!(component instanceof JComponent)) {
	return;
	}

	Point p = e.getLocation();

	if (Math.abs(p.x - lastPosition.x) > hysteresis
	\|\| Math.abs(p.y - lastPosition.y) > hysteresis) {
	// no autoscroll
	if (timer.isRunning()) timer.stop();
	} else {
	if (!timer.isRunning()) timer.start();
	}

	lastPosition = p;
	}

	public void dragExit(DropTargetEvent e) {
	cleanup(false);
	}

	public void drop(DropTargetDropEvent e) {
	TransferHandler importer =
	((HasGetTransferHandler)component).getTransferHandler();

	if (importer == null) {
	e.rejectDrop();
	cleanup(false);
	return;
	}

	support.setDNDVariables(component, e);
	boolean canImport = importer.canImport(support);

	if (canImport) {
	e.acceptDrop(support.getDropAction());

	boolean showLocation = support.showDropLocationIsSet ?
	support.showDropLocation :
	canImport;

	setComponentDropLocation(showLocation ? support : null, false);

	boolean success;

	try {
	success = importer.importData(support);
	} catch (RuntimeException re) {
	success = false;
	}

	e.dropComplete(success);
	cleanup(success);
	} else {
	e.rejectDrop();
	cleanup(false);
	}
	}

	public void dropActionChanged(DropTargetDragEvent e) {
	/*
	* Work-around for Linux bug where dropActionChanged
	* is called before dragEnter.
	*/
	if (component == null) {
	return;
	}

	handleDrag(e);
	}

	private void cleanup(boolean forDrop) {
	setComponentDropLocation(null, forDrop);
	if (component instanceof JComponent) {
	((JComponent)component).dndDone();
	}

	if (timer != null) {
	timer.stop();
	}

	state = null;
	component = null;
	lastPosition = null;
	}
	}

	/**
	* This is the default drag handler for drag and drop operations that
	* use the <code>TransferHandler</code>.
	*/
	private static class DragHandler implements DragGestureListener, DragSourceListener {

	private boolean scrolls;

	// --- DragGestureListener methods -----------------------------------

	/**
	* a Drag gesture has been recognized
	*/
	public void dragGestureRecognized(DragGestureEvent dge) {
	JComponent c = (JComponent) dge.getComponent();
	TransferHandler th = c.getTransferHandler();
	Transferable t = th.createTransferable(c);
	if (t != null) {
	scrolls = c.getAutoscrolls();
	c.setAutoscrolls(false);
	try {
	Image im = th.getDragImage();
	if (im == null) {
	dge.startDrag(null, t, this);
	} else {
	dge.startDrag(null, im, th.getDragImageOffset(), t, this);
	}
	return;
	} catch (RuntimeException re) {
	c.setAutoscrolls(scrolls);
	}
	}

	th.exportDone(c, t, NONE);
	}

	// --- DragSourceListener methods -----------------------------------

	/**
	* as the hotspot enters a platform dependent drop site
	*/
	public void dragEnter(DragSourceDragEvent dsde) {
	}

	/**
	* as the hotspot moves over a platform dependent drop site
	*/
	public void dragOver(DragSourceDragEvent dsde) {
	}

	/**
	* as the hotspot exits a platform dependent drop site
	*/
	public void dragExit(DragSourceEvent dsde) {
	}

	/**
	* as the operation completes
	*/
	public void dragDropEnd(DragSourceDropEvent dsde) {
	DragSourceContext dsc = dsde.getDragSourceContext();
	JComponent c = (JComponent)dsc.getComponent();
	if (dsde.getDropSuccess()) {
	c.getTransferHandler().exportDone(c, dsc.getTransferable(), dsde.getDropAction());
	} else {
	c.getTransferHandler().exportDone(c, dsc.getTransferable(), NONE);
	}
	c.setAutoscrolls(scrolls);
	}

	public void dropActionChanged(DragSourceDragEvent dsde) {
	}
	}

	private static class SwingDragGestureRecognizer extends DragGestureRecognizer {

	SwingDragGestureRecognizer(DragGestureListener dgl) {
	super(DragSource.getDefaultDragSource(), null, NONE, dgl);
	}

	void gestured(JComponent c, MouseEvent e, int srcActions, int action) {
	setComponent(c);
	setSourceActions(srcActions);
	appendEvent(e);
	fireDragGestureRecognized(action, e.getPoint());
	}

	/**
	* register this DragGestureRecognizer's Listeners with the Component
	*/
	protected void registerListeners() {
	}

	/**
	* unregister this DragGestureRecognizer's Listeners with the Component
	*
	* subclasses must override this method
	*/
	protected void unregisterListeners() {
	}

	}

	static final Action cutAction = new TransferAction("cut");
	static final Action copyAction = new TransferAction("copy");
	static final Action pasteAction = new TransferAction("paste");

	static class TransferAction extends UIAction implements UIResource {

	TransferAction(String name) {
	super(name);
	}

	public boolean isEnabled(Object sender) {
	if (sender instanceof JComponent
	&& ((JComponent)sender).getTransferHandler() == null) {
	return false;
	}

	return true;
	}

	private static final JavaSecurityAccess javaSecurityAccess =
	SharedSecrets.getJavaSecurityAccess();

	public void actionPerformed(final ActionEvent e) {
	final Object src = e.getSource();

	final PrivilegedAction<Void> action = new PrivilegedAction<Void>() {
	public Void run() {
	actionPerformedImpl(e);
	return null;
	}
	};

	final AccessControlContext stack = AccessController.getContext();
	final AccessControlContext srcAcc = AWTAccessor.getComponentAccessor().getAccessControlContext((Component)src);
	final AccessControlContext eventAcc = AWTAccessor.getAWTEventAccessor().getAccessControlContext(e);

	if (srcAcc == null) {
	javaSecurityAccess.doIntersectionPrivilege(action, stack, eventAcc);
	} else {
	javaSecurityAccess.doIntersectionPrivilege(
	new PrivilegedAction<Void>() {
	public Void run() {
	javaSecurityAccess.doIntersectionPrivilege(action, eventAcc);
	return null;
	}
	}, stack, srcAcc);
	}
	}

	private void actionPerformedImpl(ActionEvent e) {
	Object src = e.getSource();
	if (src instanceof JComponent) {
	JComponent c = (JComponent) src;
	TransferHandler th = c.getTransferHandler();
	Clipboard clipboard = getClipboard(c);
	String name = (String) getValue(Action.NAME);

	Transferable trans = null;

	// any of these calls may throw IllegalStateException
	try {
	if ((clipboard != null) && (th != null) && (name != null)) {
	if ("cut".equals(name)) {
	th.exportToClipboard(c, clipboard, MOVE);
	} else if ("copy".equals(name)) {
	th.exportToClipboard(c, clipboard, COPY);
	} else if ("paste".equals(name)) {
	trans = clipboard.getContents(null);
	}
	}
	} catch (IllegalStateException ise) {
	// clipboard was unavailable
	UIManager.getLookAndFeel().provideErrorFeedback(c);
	return;
	}

	// this is a paste action, import data into the component
	if (trans != null) {
	th.importData(new TransferSupport(c, trans));
	}
	}
	}

	/**
	* Returns the clipboard to use for cut/copy/paste.
	*/
	private Clipboard getClipboard(JComponent c) {
	if (SwingUtilities2.canAccessSystemClipboard()) {
	return c.getToolkit().getSystemClipboard();
	}
	Clipboard clipboard = (Clipboard)sun.awt.AppContext.getAppContext().
	get(SandboxClipboardKey);
	if (clipboard == null) {
	clipboard = new Clipboard("Sandboxed Component Clipboard");
	sun.awt.AppContext.getAppContext().put(SandboxClipboardKey,
	clipboard);
	}
	return clipboard;
	}

	/**
	* Key used in app context to lookup Clipboard to use if access to
	* System clipboard is denied.
	*/
	private static Object SandboxClipboardKey = new Object();

	}

	}

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