swingからファイルをドラッグ＆ドロップ

import java.awt.datatransfer.*;
import java.awt.dnd.*;
import java.io.File;
import java.util.ArrayList;
import javax.swing.*;

public class SwingTest implements Transferable, DragGestureListener {
    JFrame frame;
    SwingTest() {
        frame = new JFrame();
        DragSource dragSource = new DragSource();
        DragGestureRecognizer dgr = dragSource.createDefaultDragGestureRecognizer(
                    frame,
                    DnDConstants.ACTION_COPY_OR_MOVE,
                    this);
        frame.setSize(640, 480);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
    public Object getTransferData(DataFlavor flavor) {
        ArrayList filelist = new ArrayList();
        filelist.add(new File("C:/Test.txt"));
       return filelist;
    }
    public DataFlavor[] getTransferDataFlavors() {
       return new DataFlavor[] {DataFlavor.javaFileListFlavor};
    }
    public boolean isDataFlavorSupported(DataFlavor flavor) {
       return flavor.equals(DataFlavor.javaFileListFlavor);
    }
    public void dragGestureRecognized(DragGestureEvent e) {
       if((e.getDragAction()|DnDConstants.ACTION_COPY_OR_MOVE)!=0) {
           e.startDrag(DragSource.DefaultCopyDrop, this, null);
       }
    }
    public static void main(String[] args) {
        new SwingTest();
    }
}