Total not displaying in JTextArea

Hello,

I am getting an error that I think means that the total can not find
the text area that it needs to display. The error reads;

java:180: cannot find symbol
symbol : variable totalJTextArea
location: class help
                 totalJTextArea.setText(currency.format(total));

// here is the code

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

public class help extends JFrame
{
    //JLabel for business name
    private JLabel businessNameJLabel;

    // JLabel and JTextField for balance
   private JLabel balanceJLabel;
   private JTextField balanceJTextField;

   // JLabel and JTextField for interest
   private JLabel interestJLabel;
   private JTextField interestJTextField;

   // JLabel and JTextField for years
   private JLabel yearsJLabel;
   private JTextField yearsJTextField;

   // JLabel and JTextField for total
   private JLabel totalJLabel;
   private JTextField totalJTextField;

   // JButton to initiate calculation
   private JButton calculateJButton;

   // no-argument constructor
   public help()
   {
      createUserInterface();
   }

   // create and position GUI components
   public void createUserInterface()
   {
      // get content pane and set its layout
      Container container = getContentPane();
      container.setLayout( null );

      // set up businessNameJLabel
      businessNameJLabel = new JLabel();
      businessNameJLabel.setText( "Calulator" );
      businessNameJLabel.setLocation( 35, 20 );
      businessNameJLabel.setSize( 550, 88 );
      businessNameJLabel.setFont( new Font( "SansSerif", Font.PLAIN, 36
) );
      businessNameJLabel.setHorizontalAlignment( JLabel.CENTER );
      container.add( businessNameJLabel );

       // set up balanceJLabel
      balanceJLabel = new JLabel();
      balanceJLabel.setBounds( 26, 170, 134, 21 );
      balanceJLabel.setText( "Balance:" );
      container.add( balanceJLabel );

      // set up balanceJTextField
      balanceJTextField = new JTextField();
      balanceJTextField.setBounds( 120, 170, 40, 21 );
      balanceJTextField.setText( "" );
      container.add( balanceJTextField );

      // set up interestJLabel
      interestJLabel = new JLabel();
      interestJLabel.setBounds( 26, 200, 130, 21 );
      interestJLabel.setText( "Interest:" );
      container.add( interestJLabel );

      // set up interestJTextField
      interestJTextField = new JTextField();
      interestJTextField.setBounds( 120, 200, 220, 21 );
      interestJTextField.setText( "" );
      container.add( interestJTextField );

      // set up yearsJLabel
      yearsJLabel = new JLabel();
      yearsJLabel.setBounds( 26, 230, 120, 21 );
      yearsJLabel.setText( "Years:" );
      container.add( yearsJLabel );

      // set up yearsJTextField
      yearsJTextField = new JTextField();
      yearsJTextField.setBounds( 120, 230, 220, 21 );
      yearsJTextField.setText( "" );
      container.add( yearsJTextField );

      // set up totalJLabel
      totalJLabel = new JLabel();
      totalJLabel.setBounds( 260, 510, 134, 21 );
      totalJLabel.setText( "Total:" );
      container.add( totalJLabel );

      // set up totalJTextField
      totalJTextField = new JTextField();
      totalJTextField.setBounds( 360, 510, 60, 21 );
      totalJTextField.setText( "$0.00" );
      totalJTextField.setEditable( false );
      totalJTextField.setHorizontalAlignment( JTextField.CENTER );
      container.add( totalJTextField );

      // set up calculateJButton
      calculateJButton = new JButton();
      calculateJButton.setBounds( 335, 550, 90, 24 );
      calculateJButton.setText( "Calculate" );
      container.add( calculateJButton );

      calculateJButton.addActionListener(

        new ActionListener()
        {
        public void actionPerformed (ActionEvent event)
            {
                calculateJButtonActionPerformed (event);
            }
       }
    );

      // set properties of application's window
      setTitle( "Calulator" ); // set title bar text
      setSize( 650, 650 ); // set window size
      setVisible( true ); // display window

   } // end method createUserInterface

// calculate total of order

private void calculateJButtonActionPerformed ( ActionEvent event )
 {

  // declare
  //String amount = balanceJTextField.getText();
  //String interest = interestJTextField.getText();
  //String years = yearsJTextField.getText();

     // display error message if no name entered or
      // no JCheckBox is selected
      //if ( ( balance.equals( "" ) ) ||
         //( ( interest.equals( "" ) ) ||
         //( ( years.equals( "" ) ) ) ) )
      //{
         // display error message
         //JOptionPane.showMessageDialog( null,
           // "Please enter a Balance, Interest, and Years.",
            //"Missing Information", JOptionPane.ERROR_MESSAGE );
     // }
      //try // otherwise, do calculations
      //{

                int amount =
Integer.parseInt(balanceJTextField.getText());

                int interest =
Integer.parseInt(interestJTextField.getText());

                int interestYears = ( interest / 100 );

                int years =
Integer.parseInt(yearsJTextField.getText());

                double monthlyInt = (interestYears / 12);

                double paymentCount = ( years * 12 );

                double total = amount * ( monthlyInt / (1. -
Math.pow(1. + monthlyInt, - paymentCount)));

                            //double bal = new
Double(balString).doubleValue();

                           // double intyr = new Double(intString).doubleValue() /
100.;

                            //short nyears = (short)new
Integer(nyrString).intValue();

                            //double intmo = intyr / 12.;

                            //int npmts = nyears * 12;

             //double pmt = bal * (intmo / (1. - Math.pow(1. +
intmo,-npmts)));

                 DecimalFormat currency = new DecimalFormat("$0.00");
                 // Format output
                 totalJTextArea.setText(currency.format(total));
                 // Output payment amount

        //}
        //catch (NumberFormatException ex){}
    }

   // main method
   public static void main( String[] args )
   {
      help application = new help();
      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );

   } // end method main

} // end class orderForm

Thanks in advance,

Mike