Thread: Not Displaying what I need

* This program will calculate and display the monthly
* payment amount to fully amortize an input loan amount
* over a specific term at percentage of interest from a list
* selection menu of of available mortgage loans.
I've tried taken my code from the previous assignment and input that here. This is homework, just seeking help and understanding. PLEASE!!!

import java.text.NumberFormat;
 
/*Robin Williams
 * PRG/421
 * Week 3, Change Request 5
 * GUI for Mortgage Calculator with Array/Menu
 */
 
 
public class MortgageCalculatorJFrame extends javax.swing.JFrame {
 
    /** Creates new form MortgageCalculatorJFrame */
    public MortgageCalculatorJFrame() {
        initComponents();
    }
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {
 
        loanAmountLbl = new javax.swing.JLabel();
        loanChoiceLbl = new javax.swing.JLabel();
        loanAmountTxt = new javax.swing.JTextField();
        loanChoiceCmb = new javax.swing.JComboBox();
        calculateButton = new javax.swing.JButton();
        clearButton = new javax.swing.JButton();
        quitButton = new javax.swing.JButton();
        jScrollPane1 = new javax.swing.JScrollPane();
        resultsTxtArea = new javax.swing.JTextArea();
 
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
 
        loanAmountLbl.setText("Loan Amount");
 
        loanChoiceLbl.setText("Loan Choice");
 
        loanChoiceCmb.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "7 years at 5.35%", "15 years at 5.5%", "30 years at 5.75%" }));
        loanChoiceCmb.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                loanChoiceCmbActionPerformed(evt);
            }
        });
 
        calculateButton.setText("Calculate");
        calculateButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                calculateButtonActionPerformed(evt);
            }
        });
 
        clearButton.setText("Clear");
        clearButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                clearButtonActionPerformed(evt);
            }
        });
 
        quitButton.setText("Quit");
        quitButton.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                quitButtonActionPerformed(evt);
            }
        });
 
        resultsTxtArea.setColumns(20);
        resultsTxtArea.setRows(5);
        jScrollPane1.setViewportView(resultsTxtArea);
 
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(72, 72, 72)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                    .addComponent(loanAmountLbl, javax.swing.GroupLayout.PREFERRED_SIZE, 80, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(loanChoiceLbl, javax.swing.GroupLayout.PREFERRED_SIZE, 80, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(86, 86, 86)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(loanAmountTxt, javax.swing.GroupLayout.DEFAULT_SIZE, 230, Short.MAX_VALUE)
                            .addComponent(loanChoiceCmb, javax.swing.GroupLayout.Alignment.TRAILING, 0, 230, Short.MAX_VALUE)))
                    .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addComponent(clearButton, javax.swing.GroupLayout.PREFERRED_SIZE, 80, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addGap(100, 100, 100)
                        .addComponent(quitButton, javax.swing.GroupLayout.PREFERRED_SIZE, 86, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addGap(54, 54, 54))
            .addGroup(layout.createSequentialGroup()
                .addGap(28, 28, 28)
                .addComponent(calculateButton)
                .addContainerGap(377, Short.MAX_VALUE))
            .addGroup(layout.createSequentialGroup()
                .addGap(55, 55, 55)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 377, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(50, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(47, 47, 47)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(loanAmountLbl, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(loanAmountTxt, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(59, 59, 59)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(loanChoiceLbl, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(loanChoiceCmb, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(29, 29, 29)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(calculateButton)
                    .addComponent(quitButton)
                    .addComponent(clearButton))
                .addGap(34, 34, 34)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 134, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(23, Short.MAX_VALUE))
        );
 
        pack();
    }// </editor-fold>                        
 
    private void loanChoiceCmbActionPerformed(java.awt.event.ActionEvent evt) {                                              
 
    }                                             
 
    @SuppressWarnings("empty-statement")
    private void calculateButtonActionPerformed(java.awt.event.ActionEvent evt) {                                                
 
        double dblPrincipal = (Double.parseDouble (loanAmountTxt.getText()));                  //principal amount
        double [] dblInterestRate = {5.35,5.5,5.75};     //intialized the array with values(interest rate)
        int []intLoanTermYear  = {7,15,30};              //intialized the array with values(loan term)
        double [] dblMonthlyPayment = {0,0,0};            //intialized the array with zero values(monthly payment)
        double [] dblMonthlyInterestRate= {0,0,0};        //intialized the array with zero values(monthly interest rate)
        int [] intLoanTermMonth = {0,0,0};               //intialized the array with zero values(loan term in months)
        int box = loanChoiceCmb.getSelectedIndex();
        double dblcurrentbalance = 0;
        double dblcurrentmonthlyPrincipalpayment = 0;
        double dblcurrentmonthlyInterestpaid = 0;
        double dblcurrentmonthlyprincipal = 0;
        double dblpreviousmonthlybalance = 0;
 
        {
 
            dblMonthlyInterestRate[box] = dblInterestRate[box]/(12 * 100); //calculate monthly interest rate per array
 
 
            intLoanTermMonth[box] = intLoanTermYear[box] * 12;             //calculate number of months of loan
 
            /* Monthlypayment formula using array index values */
            dblMonthlyPayment[box] = dblPrincipal * ( dblMonthlyInterestRate[box] / (1 - (Math.pow((1 + dblMonthlyInterestRate[box]),-(intLoanTermMonth[box])))));
 
            /* Calculation formulas*/
                dblcurrentmonthlyInterestpaid = (dblPrincipal * dblMonthlyInterestRate[box]);          //current monthly interest
                dblcurrentmonthlyPrincipalpayment = (dblMonthlyPayment[box] - dblMonthlyInterestRate[box]); //current monthlt principal payment
                dblcurrentmonthlyprincipal = (dblPrincipal - dblcurrentbalance);                               //calculate the new balance
                dblpreviousmonthlybalance =  dblcurrentmonthlyprincipal;
 
 
                int intlinecounter=1;
 
                for(intlinecounter=1; intlinecounter<=intLoanTermMonth[box]; intlinecounter++)
                {
               // Formulas to perform calculations
                  dblMonthlyInterestRate[box] = dblpreviousmonthlybalance * dblMonthlyInterestRate[box];
                  dblcurrentbalance = dblMonthlyPayment[box] - dblcurrentmonthlyInterestpaid;
                  dblcurrentmonthlyprincipal = dblpreviousmonthlybalance - dblcurrentbalance;
                  dblpreviousmonthlybalance = dblcurrentmonthlyprincipal;
 
//Print out Monthly Payment Amount
            NumberFormat CurrencyFormat = NumberFormat.getCurrencyInstance();
resultsTxtArea.append("The Loan Principal is " +(CurrencyFormat.format (dblPrincipal))+ "." + "\n"+"The loan's interest rate is" +""+"" + dblInterestRate[box] +"%." + "\n"+"The loan term is"+""+intLoanTermYear[box]+""+ "years."+"\n"+"The monthly payment will be"+""+(CurrencyFormat.format (dblMonthlyPayment[box])));
 
           if(intlinecounter % 20 == 0)
{              intlinecounter=1;
               System.out.println("Press any key to continue");
                                try
                                {  System.in.read();
                                }catch (Exception e){;
                                        }
 
 
 
        }
                }}
    }                                               
    private void quitButtonActionPerformed(java.awt.event.ActionEvent evt) {                                           
       System.exit(0);
    }                                          
 
    private void clearButtonActionPerformed(java.awt.event.ActionEvent evt) {                                            
        loanAmountTxt.setText(null);
        loanChoiceCmb.setSelectedIndex(-1);
        resultsTxtArea.setText(null);
    }                                           
 
    /**
    * @param args the command line arguments
    */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new MortgageCalculatorJFrame().setVisible(true);
            }
        });
    }
 
    // Variables declaration - do not modify                     
    private javax.swing.JButton calculateButton;
    private javax.swing.JButton clearButton;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JLabel loanAmountLbl;
    private javax.swing.JTextField loanAmountTxt;
    private javax.swing.JComboBox loanChoiceCmb;
    private javax.swing.JLabel loanChoiceLbl;
    private javax.swing.JButton quitButton;
    private javax.swing.JTextArea resultsTxtArea;
    // End of variables declaration                   
 
}

More information is needed. Any compile time or runtime errors? Are you receiving an output different than you would expect? If so, describe in all its detail.