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

// This example demonstrates the use of JButton, JTextField
// and JLabel.
public class ConvertText implements ActionListener, MouseListener{

 JFrame convertTextFrame;
    JPanel convertTextPanel;
    JTextField enterString;
    JLabel enterAString;
    JButton upper, lower;

 // Constructor
    public ConvertText()
        {
            // Create the frame and container.
            convertTextFrame = new JFrame("Convert String");
            convertTextPanel = new JPanel();
            convertTextPanel.setLayout(new GridLayout(2,2));

            // Add the widgets.
            addWidgets();

            // Add the panel to the frame.
            convertTextFrame.getContentPane().add(convertTextPanel, BorderLayout.CENTER);

            // Exit when the window is closed.
            convertTextFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            // Show the converter.
            convertTextFrame.pack();
            convertTextFrame.setVisible(true);
  				
			 upper.addMouseListener( this );  
			 lower.addMouseListener(this);
	 }

 // Create and add the widgets for converter.
    private void addWidgets()
        {
            // Create widgets.
     			enterAString = new JLabel("Enter A String", SwingConstants.LEFT);      
				upper = new JButton("Upper");      
			 	enterString = new JTextField(2);
			 	lower = new JButton("Lower");
					 
				

            // Listen to events from the buttons.
            upper.addActionListener(this);
				lower.addActionListener(this);
            
				// Add widgets to container.
            convertTextPanel.add(enterAString);
    			convertTextPanel.add(upper);
				convertTextPanel.add(enterString);
				convertTextPanel.add(lower);	  				
 				
				enterAString.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    }
 // Implementation of ActionListener interface.
    public void actionPerformed(ActionEvent event)
        {
			if (event.getSource() instanceof JButton){
    			
				JButton clickedButton = (JButton) event.getSource();
				String buttonText = clickedButton.getText();
				
			if (buttonText.equals("Upper")){ 
				for (int i = 0; i < enterString.length; i++) {
                 enterString[i] = Character.toUpperCase(enterString[i]);
             }
				}
			else {
				for (int i = 0; i < enterString.length; i++) {
                 enterString[i] = Character.toLowerCase(enterString[i]);
             }
			}
	}
 	else {}
 
 	}
 
  public void mouseClicked(MouseEvent e){}
  public void mouseEntered(MouseEvent e){}
  public void mouseExited(MouseEvent e){ }
  public void mouseReleased(MouseEvent e){}
  public void mousePressed(MouseEvent e){ }

		 // main method
    public static void main(String[] args)
        {
            // Set the look and feel.
            try
            {
                UIManager.setLookAndFeel(
                    UIManager.getCrossPlatformLookAndFeelClassName());
            }
            catch(ClassNotFoundException e){ }
            catch(InstantiationException e){ }
            catch(IllegalAccessException e){ }
            catch(UnsupportedLookAndFeelException e){ }

            ConvertText convert = new ConvertText();
    }




}