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	/*
	* Copyright (c) 1997, 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 java.awt.dnd;

	import java.awt.Point;

	import java.awt.datatransfer.DataFlavor;
	import java.awt.datatransfer.Transferable;

	import java.util.List;

	/**
	* The <code>DropTargetDragEvent</code> is delivered to a
	* <code>DropTargetListener</code> via its
	* dragEnter() and dragOver() methods.
	* <p>
	* The <code>DropTargetDragEvent</code> reports the <i>source drop actions</i>
	* and the <i>user drop action</i> that reflect the current state of
	* the drag operation.
	* <p>
	* <i>Source drop actions</i> is a bitwise mask of <code>DnDConstants</code>
	* that represents the set of drop actions supported by the drag source for
	* this drag operation.
	* <p>
	* <i>User drop action</i> depends on the drop actions supported by the drag
	* source and the drop action selected by the user. The user can select a drop
	* action by pressing modifier keys during the drag operation:
	* <pre>
	* Ctrl + Shift -> ACTION_LINK
	* Ctrl -> ACTION_COPY
	* Shift -> ACTION_MOVE
	* </pre>
	* If the user selects a drop action, the <i>user drop action</i> is one of
	* <code>DnDConstants</code> that represents the selected drop action if this
	* drop action is supported by the drag source or
	* <code>DnDConstants.ACTION_NONE</code> if this drop action is not supported
	* by the drag source.
	* <p>
	* If the user doesn't select a drop action, the set of
	* <code>DnDConstants</code> that represents the set of drop actions supported
	* by the drag source is searched for <code>DnDConstants.ACTION_MOVE</code>,
	* then for <code>DnDConstants.ACTION_COPY</code>, then for
	* <code>DnDConstants.ACTION_LINK</code> and the <i>user drop action</i> is the
	* first constant found. If no constant is found the <i>user drop action</i>
	* is <code>DnDConstants.ACTION_NONE</code>.
	*
	* @since 1.2
	*/

	public class DropTargetDragEvent extends DropTargetEvent {

	private static final long serialVersionUID = -8422265619058953682L;

	/**
	* Construct a <code>DropTargetDragEvent</code> given the
	* <code>DropTargetContext</code> for this operation,
	* the location of the "Drag" <code>Cursor</code>'s hotspot
	* in the <code>Component</code>'s coordinates, the
	* user drop action, and the source drop actions.
	* <P>
	* @param dtc The DropTargetContext for this operation
	* @param cursorLocn The location of the "Drag" Cursor's
	* hotspot in Component coordinates
	* @param dropAction The user drop action
	* @param srcActions The source drop actions
	*
	* @throws NullPointerException if cursorLocn is null
	* @throws IllegalArgumentException if dropAction is not one of
	* <code>DnDConstants</code>.
	* @throws IllegalArgumentException if srcActions is not
	* a bitwise mask of <code>DnDConstants</code>.
	* @throws IllegalArgumentException if dtc is <code>null</code>.
	*/

	public DropTargetDragEvent(DropTargetContext dtc, Point cursorLocn, int dropAction, int srcActions) {
	super(dtc);

	if (cursorLocn == null) throw new NullPointerException("cursorLocn");

	if (dropAction != DnDConstants.ACTION_NONE &&
	dropAction != DnDConstants.ACTION_COPY &&
	dropAction != DnDConstants.ACTION_MOVE &&
	dropAction != DnDConstants.ACTION_LINK
	) throw new IllegalArgumentException("dropAction" + dropAction);

	if ((srcActions & ~(DnDConstants.ACTION_COPY_OR_MOVE \| DnDConstants.ACTION_LINK)) != 0) throw new IllegalArgumentException("srcActions");

	location = cursorLocn;
	actions = srcActions;
	this.dropAction = dropAction;
	}

	/**
	* This method returns a <code>Point</code>
	* indicating the <code>Cursor</code>'s current
	* location within the <code>Component'</code>s
	* coordinates.
	* <P>
	* @return the current cursor location in
	* <code>Component</code>'s coords.
	*/

	public Point getLocation() {
	return location;
	}


	/**
	* This method returns the current <code>DataFlavor</code>s from the
	* <code>DropTargetContext</code>.
	* <P>
	* @return current DataFlavors from the DropTargetContext
	*/

	public DataFlavor[] getCurrentDataFlavors() {
	return getDropTargetContext().getCurrentDataFlavors();
	}

	/**
	* This method returns the current <code>DataFlavor</code>s
	* as a <code>java.util.List</code>
	* <P>
	* @return a <code>java.util.List</code> of the Current <code>DataFlavor</code>s
	*/

	public List<DataFlavor> getCurrentDataFlavorsAsList() {
	return getDropTargetContext().getCurrentDataFlavorsAsList();
	}

	/**
	* This method returns a <code>boolean</code> indicating
	* if the specified <code>DataFlavor</code> is supported.
	* <P>
	* @param df the <code>DataFlavor</code> to test
	* <P>
	* @return if a particular DataFlavor is supported
	*/

	public boolean isDataFlavorSupported(DataFlavor df) {
	return getDropTargetContext().isDataFlavorSupported(df);
	}

	/**
	* This method returns the source drop actions.
	*
	* @return the source drop actions
	*/
	public int getSourceActions() { return actions; }

	/**
	* This method returns the user drop action.
	*
	* @return the user drop action
	*/
	public int getDropAction() { return dropAction; }

	/**
	* This method returns the Transferable object that represents
	* the data associated with the current drag operation.
	*
	* @return the Transferable associated with the drag operation
	* @throws InvalidDnDOperationException if the data associated with the drag
	* operation is not available
	*
	* @since 1.5
	*/
	public Transferable getTransferable() {
	return getDropTargetContext().getTransferable();
	}

	/**
	* Accepts the drag.
	*
	* This method should be called from a
	* <code>DropTargetListeners</code> <code>dragEnter</code>,
	* <code>dragOver</code>, and <code>dropActionChanged</code>
	* methods if the implementation wishes to accept an operation
	* from the srcActions other than the one selected by
	* the user as represented by the <code>dropAction</code>.
	*
	* @param dragOperation the operation accepted by the target
	*/
	public void acceptDrag(int dragOperation) {
	getDropTargetContext().acceptDrag(dragOperation);
	}

	/**
	* Rejects the drag as a result of examining either the
	* <code>dropAction</code> or the available <code>DataFlavor</code>
	* types.
	*/
	public void rejectDrag() {
	getDropTargetContext().rejectDrag();
	}

	/*
	* fields
	*/

	/**
	* The location of the drag cursor's hotspot in Component coordinates.
	*
	* @serial
	*/
	private Point location;

	/**
	* The source drop actions.
	*
	* @serial
	*/
	private int actions;

	/**
	* The user drop action.
	*
	* @serial
	*/
	private int dropAction;
	}

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