import java.util.* ;
import java.io.* ;
import java.awt.* ;
import java.awt.event.* ;
import javax.swing.* ;
import javax.swing.event.* ;

class TerminationListener implements WindowListener {
    public void windowActivated(WindowEvent e) {}
    public void windowClosed(WindowEvent e) {}
    public void windowClosing(WindowEvent e) {
        System.exit(0) ;
    }
    public void windowDeactivated(WindowEvent e) {}
    public void windowDeiconified(WindowEvent e) {}
    public void windowIconified(WindowEvent e) {}
    public void windowOpened(WindowEvent e) {}
}

class TextFieldPanel extends JPanel implements DocumentListener {

    public TextFieldPanel() {

        input = new JTextField(20) ;
        input.getDocument().addDocumentListener(this) ;
        add(input) ;

        display = new JTextField(20) ;
        display.setEditable(false) ;
        add(display) ;
    }

    public void changedUpdate(DocumentEvent evt) {
    }

    public void insertUpdate(DocumentEvent evt) {
        display.setText(input.getText()) ;
    }

    public void removeUpdate(DocumentEvent evt) {
        display.setText(input.getText()) ;
    }

    private JTextField input, display ;
}

public class TextFieldTest {
    public static void main(String [] args) {

        JFrame frame = new JFrame() ;

        frame.setTitle("TextField") ;
        frame.setSize(450, 300) ;

        frame.addWindowListener(new TerminationListener()) ;

        frame.getContentPane().add(new TextFieldPanel()) ;

        frame.setVisible(true) ;
    }
}