Hi,
I have posted my code for an interface  if anyone can help.  I have to
create an interface for employees pay.  I think i need to create an
instance of the object (object names are Employee, SalariedEmployee,
CommissionEmployee and BasePlusCommission)for each type of employee but

not sure.
Ian

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

public interface Payable
{
double getPaymentAmout();

}

public class MyPanel extends JFrame implements ActionListener
{
   private JLabel labelfirstname;//
   private JTextField first;
   private JLabel labellastname;
   private JTextField last;
   private JLabel labelssn;
   private JTextField ssn;
   private JLabel labelhoursworked;
   private JLabel labelrateofpay;
   private JTextField hoursWorked;
   private JTextField rateOfPay;
   private JLabel labelsalary;
   private JTextField salary;
   private JLabel labeltotalsales;
   private JLabel labelcommission;
   private JTextField totalSales;
   private JTextField commission;
   private JButton buttonSubmit;
   private JLabel labeltype;
   private JComboBox type;
   private JLabel labeltext;
   private JTextArea textareaResults;
   private JLabel labelrenumeration;

   public MyPanel(String str)
   {
       super(str);

       //construct preComponents
       String[] typeItems = {"Hourly", "Salary", "Commission", "Base
plus Commission"};

       Container c = getContentPane();
       c.setLayout(null);
       setSize(850,650);
       setLocationRelativeTo(null);

       //construct components
       labelfirstname = new JLabel ("  First Name");
       add (labelfirstname);
       first = new JTextField (5);
       add (first);
       labellastname = new JLabel ("  Last Name");
       add (labellastname);
       last = new JTextField (5);
       add (last);
       labelssn = new JLabel ("  Social Security Number");
       add (labelssn);
       ssn = new JTextField (5);
       add (ssn);
       labelhoursworked = new JLabel ("  Hours Worked");
       add (labelhoursworked);
       labelrateofpay = new JLabel ("  Rate of Pay");
       add (labelrateofpay);
       hoursWorked = new JTextField (5);
       add (hoursWorked);
       rateOfPay = new JTextField (5);
       add (rateOfPay);
       labelsalary = new JLabel ("  Salary");
       add (labelsalary);
       salary = new JTextField (5);
       add (salary);
       labeltotalsales = new JLabel ("  Total Sales");
       add (labeltotalsales);
       labelcommission = new JLabel ("  Commission Rate");
       add (labelcommission);
       totalSales = new JTextField (5);
       add (totalSales);
       commission = new JTextField (5);
       add (commission);
       buttonSubmit = new JButton ("SUBMIT");
       add (buttonSubmit);
       labeltype = new JLabel (" Type of Employee");
       add (labeltype);
       type = new JComboBox (typeItems);
       add (type);
       labeltext = new JLabel ("  Please fill in only text boxes
appropriate to the type of Employee");
       add (labeltext);
       textareaResults = new JTextArea (5, 5);
       add (textareaResults);
       labelrenumeration = new JLabel ("  Renumeration");
       add (labelrenumeration);
       //adjust size and set layout
       setPreferredSize (new Dimension (646, 571));
       setLayout (null);

       //set component bounds (only needed by Absolute Positioning)
       labelfirstname.setBounds (15, 31, 72, 25);
       first.setBounds (90, 31, 110, 25);
       labellastname.setBounds (214, 31, 71, 25);
       last.setBounds (285, 31, 100, 25);
       labelssn.setBounds (400, 31, 144, 25);
       ssn.setBounds (545, 31, 100, 25);
       labelhoursworked.setBounds (15, 250, 100, 25);
       labelrateofpay.setBounds (225, 250, 76, 25);
       hoursWorked.setBounds (110, 250, 100, 25);
       rateOfPay.setBounds (305, 250, 100, 25);
       labelsalary.setBounds (10, 315, 51, 25);
       salary.setBounds (60, 315, 100, 25);
       labeltotalsales.setBounds (170, 315, 100, 25);
       labelcommission.setBounds (379, 315, 112, 25);
       totalSales.setBounds (246, 315, 100, 25);
       commission.setBounds (494, 315, 100, 25);
       buttonSubmit.setBounds (505, 350, 100, 25);
       labeltype.setBounds (15, 110, 110, 20);
       type.setBounds (125, 105, 135, 25);
       labeltext.setBounds (15, 185, 370, 25);
       textareaResults.setBounds (50, 410, 565, 140);
       labelrenumeration.setBounds (50, 385, 100, 25);

   //register event handlers

       buttonSubmit.addActionListener( this );

   }//end MyPanel constuctor

       //process events

       public void actionPerformed( ActionEvent event)
       {

   if (event.getSource() == buttonSubmit)

   {
                       //Enabling the Text Area's
                       first.setEnabled (true);
               last.setEnabled (true);
               ssn.setEnabled (true);
               type.setEnabled (true);
               hoursWorked.setEnabled (true);
               rateOfPay.setEnabled (true);
               salary.setEnabled (true);
               totalSales.setEnabled (true);
               commission.setEnabled (true);

                //Setting the Text Area's to Null
               first.setText("");
               last.setText("");
               ssn.setText("");
               //type.setText("");
               hoursWorked.setText("");
               rateOfPay.setText("");
               salary.setText("");
               totalSales.setText("");
               commission.setText("");

               }

     // create subclass objects

    // SalariedEmployee salariedEmployee =  new SalariedEmployee;

     //HourlyEmployee hourlyEmployee = new HourlyEmployee();

    // CommissionEmployee commissionEmployee =   new
CommissionEmployee();

     //BasePlusCommissionEmployee basePlusCommissionEmployee =  new
BasePlusCommissionEmployee();

}

   public static void main (String[] args)
   {

       MyPanel pr = new MyPanel("ww");
       pr.show();
       //JFrame frame = new JFrame ("MyPanel");
       //frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
       //frame.getContentPane().add (new MyPanel());
       //frame.pack();
       //frame.setVisible (true);
   }

}

//