Java Code

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class DebugValue extends JApplet
                                implements ItemListener 
{
   double cat = 4;
   double dog = 10;
   double horse = 350;
   double costOfItem = 0;
   double quantity;
   JComboBox list;
   JTextField qty;
   JLabel price;
   public void init( )
   {
	setLayout( new FlowLayout( ) );
	qty = new JTextField( 4 );
   	list = new JComboBox( );
	price = new JLabel( "0.0" );
	list.addItem( "cat" );
	list.addItem( "dog" );
	list.addItem( "horse" );
	list.addItemListener( this );
	add( qty ); 
	add( list );
	add( price );
   }
   public void itemStateChanged( ItemEvent ie )
   {
	Object src = ie.getSource( );
   	if( ie.getStateChange( )==ItemEvent.SELECTED)
	{
	    if( src == list )
	    {
		quantity = Integer.parseInt( qty.getText( ) ); 
		System.out.println( "qty=" + quantity );
		System.out.println( "cost="+costOfItem);
		double totalCost = costOfItem * quantity; 
		System.out.println( "total=" + totalCost );
	    	price.setText( "" + totalCost );
	    }
	}
   }
}