import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import java.awt.datatransfer.*;
import javax.swing.*;

public class ClipboardTest extends JFrame implements ClipboardOwner {
    private Clipboard clipboard;
    private JTextField copyFrom;
    private JTextArea  copyTo;
    private JButton    copy, paste;
    
    public ClipboardTest() {
	// Obtain a reference to the system clipboard
	clipboard = getToolkit().getSystemClipboard();
	
	//Create the GUI.
	copyFrom  = new JTextField(20);
	copyTo    = new JTextArea(3, 20);
	copy      = new JButton("Copy To System Clipboard");
	paste     = new JButton("Paste From System Clipboard");
	Container c = getContentPane();
	c.setLayout(new FlowLayout());
	c.add(copyFrom);
	c.add(copy);
	c.add(paste);
	c.add(copyTo);
	
	copy.addActionListener (new CopyListener());
	paste.addActionListener(new PasteListener());
	
	//Show the frame.
	setSize(300, 200);
	addWindowListener(new WindowAdapter() {
	    public void windowClosing(WindowEvent e) {
		System.exit(0);
	    }
	});
	setVisible(true);
    }
    
    class CopyListener implements ActionListener {
	
	public void actionPerformed(ActionEvent event) {
	    //This is were the string is copied to the system
	    //clipboard.
	    
	    //Create a transferable object that contains the
	    //string we are copying.
	    StringSelection contents = 
		new StringSelection(copyFrom.getText());
	    
	    // Place the transferable onto the clipboard.	
	    clipboard.setContents(contents, ClipboardTest.this);
	    
	}
	
    }
    
    class PasteListener implements ActionListener {
	
	public void actionPerformed(ActionEvent event) {
	    //This is were a string is read from the
	    //system clipboard.
	    
	    //Get the content of the clipboard.
	    Transferable contents = clipboard.getContents(this);
	    
	    // Determine if data is available in string flavor 
	    if(contents != null && 
	       contents.isDataFlavorSupported(
					      DataFlavor.stringFlavor)) {
		try {
		    String string;
		    
		    // Have contents cough up the string
		    // that was placed on the clipboard.
		    string = (String) contents.getTransferData(
						 DataFlavor.stringFlavor);
		    copyTo.append(string);
		}
		catch(Exception e) {
		    e.printStackTrace();
		}
	    }
	}
	
    }
    
    public void lostOwnership(Clipboard clip, Transferable transferable) {
	//We must keep the object we placed on the system clipboard
	//until this method is called.
	
	System.out.println("Lost ownership");
    }
    
    public static void main(String[] args) {
	new ClipboardTest();
    }
    
}