problem with java assignment

[jaire]

I am working on a mortgage calculator for my java class. I have the payment calculation correct, but I cannot figure out why the balance figure is working. I had this working at the system level without a gui and it showed the interest and balance after each payment. Now it only shows the last one and it doesn't look like it is a repeating statement. Plus the scroll box at the bottom is not scrolling the right way. Please help if you can.

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;

public class jTaylor3 extends JFrame implements ActionListener {

	// Define labels, fields and buttons	
	JPanel mortgageAmountPanel = new JPanel( new GridLayout( 1, 5 ) );
	JLabel mortgageAmountLabel = new JLabel( "Mortgage Amount", JLabel.LEFT );
	JTextField mortgageAmountField = new JTextField( 10 );
		
	JPanel termYearsPanel = new JPanel( new GridLayout( 1, 5 ) );
	JLabel termYearsLabel = new JLabel( "Terms in Years", JLabel.LEFT );
	JTextField termYearsField = new JTextField( 10 );
		
	JPanel interestRatePanel = new JPanel( new GridLayout( 1, 5 ) );
	JLabel interestRateLabel = new JLabel( "Interest Rate", JLabel.LEFT );
	JTextField interestRateField = new JTextField( 10 );
		
	JPanel monthPaymentPanel = new JPanel( new GridLayout( 1, 5 ) );
	JLabel monthPaymentLabel = new JLabel( "Monthly Payment $:", JLabel.LEFT );
	JTextField monthPaymentField = new JTextField( 10 );
	
	JPanel payDetailPanel = new JPanel( new GridLayout( 15, 15 ) );
	JLabel payDetailLabel = new JLabel( "Payment   Interest Paid       Balance", JLabel.LEFT );
	JTextField payDetailField = new JTextField( 100 );
	
	JPanel button = new JPanel( new GridLayout( 3,3 ) );
	
	


	// Create buttons
	JButton calcButton1 = new JButton( "Calculate 7 years at 5.35%" );
	JButton calcButton2 = new JButton( "Calculate 15 years at 5.5%" );
	JButton calcButton3 = new JButton( "Calculate 30 years at 5.75%" );

	// Create area for user input
	JTextArea displayArea = new JTextArea( 10, 25 );

	// Declare variables and text formatting
	double rate = 0;
	double monthPayment = 0;
	double mortgageAmount = 200000;
	int termYears = 30;
	double interestRate = 3.75;
	DecimalFormat valueFormat = new DecimalFormat( "#,###.00" );

public jTaylor3() {
	super( "MORTGAGE CALCULATOR 1.0" );
	setSize( 300, 380 );// sets size of the constructor
	setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
	
	// Add content to panels
	Container pane = getContentPane();// return value of content
	pane.add( mortgageAmountPanel );
		mortgageAmountPanel.add( mortgageAmountLabel );
		mortgageAmountPanel.add( mortgageAmountField );
		mortgageAmountPanel.setMaximumSize( new Dimension( 250, 25 ) );
		
	button.add( calcButton1);
	pane.add( button );
		setVisible( true );
		setContentPane( pane );
		button.setMaximumSize( new Dimension( 250, button.getMinimumSize().height ) );
		calcButton1.addActionListener( this );
	
	button.add( calcButton2);
	pane.add( button );
		pane.setLayout( new BoxLayout( pane, BoxLayout.Y_AXIS ) );
		setVisible( true );
		setContentPane( pane );
		button.setMaximumSize( new Dimension( 250, button.getMinimumSize().height ) );
		calcButton2.addActionListener( this );
	
	button.add( calcButton3);
	pane.add( button );
		pane.setLayout( new BoxLayout( pane, BoxLayout.Y_AXIS ) );
		setVisible( true );
		setContentPane( pane );
		button.setMaximumSize( new Dimension( 250, button.getMinimumSize().height ) );
		calcButton3.addActionListener( this );
	
	pane.add( monthPaymentPanel );
		monthPaymentPanel.add( monthPaymentLabel );
		monthPaymentPanel.add( monthPaymentField );
		monthPaymentPanel.setMaximumSize( new Dimension( 250, monthPaymentPanel.getMinimumSize().height ) );
	
	pane.add( payDetailPanel );
		payDetailPanel.add( payDetailLabel );
		payDetailPanel.setMaximumSize( new Dimension( 250, payDetailPanel.getMinimumSize().height ) );


		JScrollPane scrollPane = new JScrollPane(payDetailField);
	add(scrollPane, BorderLayout.CENTER);	

	
}

// Define action event
public void actionPerformed( ActionEvent event ) {
	Object source = event.getSource();
	int counter = 0;
	
   if( source == calcButton1 ) {
   	String mA = mortgageAmountField.getText();
   	double mortAmt = Double.valueOf(mA);
   	double monthInterest1 = ((5.35 / 12) / 100);
   	double numPeriods1 = 7*12;       
   	double monthPmt1 = mortAmt * ( monthInterest1 /(1 - Math.pow(1 + monthInterest1, -numPeriods1)));

	monthPaymentField.setText(valueFormat.format(monthPmt1));
	
	//while statement to calculate monthly interest and balance on first button
	while (counter <= 2) {
   	   String mA2 = mortgageAmountField.getText();
   	   double mortAmt2 = Double.valueOf(mA2);
   	   double monthPmt2 = mortAmt2 * ( monthInterest1 /(1 - Math.pow(1 + monthInterest1, -numPeriods1)));
   	   double Balance0 = mortAmt2 * ((1 + monthInterest1) - monthPmt2); //Balance calculation
           double Interest0 = mortAmt2 * monthInterest1; //Interest calculation
           
           payDetailField.setText(" " + counter + "               "  + (valueFormat.format(Interest0))+ "               " + (valueFormat.format(Balance0)));
                
           mortAmt2 = Balance0; //Balance of previous month
           counter++; //Increment counter after each payment

		}//End of while statement
   }//End of calcButton1 if statement
   
   if( source == calcButton2 ) {
   	   String mA = mortgageAmountField.getText();
   	   double mortAmt = Double.valueOf(mA);
   	   double monthInterest1 = ((5.5 / 12) / 100);
   	   double numPeriods1 = 15*12;       
   	   double monthPmt1 = mortAmt * ( monthInterest1 /(1 - Math.pow(1 + monthInterest1, -numPeriods1)));

   	   monthPaymentField.setText(valueFormat.format(monthPmt1));
   
   }//End of calcButton2 if statement
   
   if( source == calcButton3) {
   	   String mA = mortgageAmountField.getText();
   	   double mortAmt = Double.valueOf(mA);
   	   double monthInterest1 = ((5.75 / 12) / 100);
   	   double numPeriods1 = 30*12;       
   	   double monthPmt1 = mortAmt * ( monthInterest1 /(1 - Math.pow(1 + monthInterest1, -numPeriods1)));

   	   monthPaymentField.setText(valueFormat.format(monthPmt1));
  
   }//End of calcButton3 if statement
}//End of Action event

public static void main( String[] arguments ) {
	jTaylor3 mtg = new jTaylor3();
	
}//End of main class

// Declaration of user input for each variable
public void validateUserInput( JTextField mortgageAmountField, JTextField interestRateField, JTextField termYearsField ) {

	}//End of input validation
}

[sunde887]

Use code tags.

[ code]
Your code
[/code]

Remove the space in [ code] also.

[jaire]

Do you mean in the post itself, or in my code? Thanks.

[sunde887]

In the post so I can read your code more easily.

[jaire]

I apologize for my ignorance, but are you just needing an indication of where the code starts and ends in the post?

[Eranga]

@OP, you can edit the post and insert code tags. Don't post it again.

[Eranga]

I apologize for my ignorance, but are you just needing an indication of where the code starts and ends in the post?

I've done it for you this time only. But please pay your attention next time. It may off topic to the original if I explain how to use code tags in details right now. So please have a look my forum signature, you can find the relevant FAQ section to do that. Please read it before posting a code segment again.

[jaire]

The post is edited with the code tags. I see what you're saying now. I'm new to this forum as well.

[Eranga]

Never mind.

So what's your question here. If you could explain in a simple way we can help you more. Because your code is too long and hard to read. Could be specific, please?

[jaire]

How do I get the jscroll pane the same size as the other fields? Does it need to go in a different spot in the code or is there a way to adjust it? Also, I am trying to get a list of interest paid and balance for each payment, but I just get one calculation.