I am trying to add a chart to my mortgage calculator having some errors. If anyone can help figure out my errors i be so grateful. The assignment is due at midnite.
Code:
/*
* * @(#)Calculator.java
*
*
* @author Mike Souza
* @version 1.00 2011/18/10
Change Request #7
Requestor: Ninfa Pendleton - Rapid City, SD
Write the program in Java (with a graphical user interface) and
* have it calculate and display the mortgage payment amount from
* user input of the amount of the mortgage and the user's
* selection from a menu of available mortgage loans:
- 7 years at 5.35%
- 15 years at 5.5%
- 30 years at 5.75%
Use an array for the mortgage data for the different loans.
* Read the interest rates to fill the array from a sequential
* file. Display the mortgage payment amount followed by the loan
* balance and interest paid for each payment over the term of the
* loan. Add graphics in the form of a chart. Allow the user to
* loop back and enter a new amount and make a new selection or
* quit. Please insert comments in the program to document the
* program.
*/
import java.awt.*;
import java.text.NumberFormat;
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.Graphics2D;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.geom.Line2D;
public class Calculator extends JFrame implements ActionListener
{
//Array
int terms[] = { 7, 15, 30 };
double rates[] = { 5.35, 5.5, 5.75 };
//Labels Declared here
JLabel AmountLabel = new JLabel("Amount of loan");
JLabel PaymentLabel = new JLabel("Monthly Payment");
JLabel InterestLabel = new JLabel("Interest Rate");
JLabel TermLabel = new JLabel("Loan Term");
//Text field
JTextField mortgageAmount = new JTextField(7);
JTextField Payment = new JTextField(7);
JTextField InterestRate = new JTextField(3);
JTextField Term = new JTextField(3);
//Buttons here
JButton Loan7 = new JButton("7 years at 5.35%");
JButton Loan15 = new JButton("15 years at 5.50%");
JButton Loan30 = new JButton("30 years at 5.75%");
JButton ExitButton = new JButton("Exit");
JButton ClearButton = new JButton("Clear All");
JButton CalculateButton = new JButton("Calculate Loan");
//text and scroll here
JTextArea LoanPayments = new JTextArea(20, 50);
JTextArea GraphArea = new JTextArea(19, 50);
JScrollPane scroll = new JScrollPane(LoanPayments);
public Calculator()
{
//panel and frame
super("Mortgage Calculator");
setSize(700, 500);
setLocation(200, 0);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel pane = new JPanel(new GridLayout(2, 1));
//content for container
Container grid = getContentPane();
grid.setLayout(new GridLayout(4, 0, 4, 4));
pane.add(grid);
pane.add(scroll);
grid.add(AmountLabel);
grid.add(mortgageAmount);
grid.add(InterestLabel);
grid.add(InterestRate);
grid.add(TermLabel);
grid.add(Term);
grid.add(PaymentLabel);
grid.add(Payment);
grid.add(Loan7);
grid.add(Loan15);
grid.add(Loan30);
grid.add(CalculateButton);
grid.add(ClearButton);
grid.add(ExitButton);
Payment.setEditable(false);
setContentPane(pane);
setContentPane(pane);
setVisible(true);
//Acton Listeners
ExitButton.addActionListener(this);
ClearButton.addActionListener(this);
Loan7.addActionListener(this);
Loan15.addActionListener(this);
Loan30.addActionListener(this);
mortgageAmount.addActionListener(this);
InterestRate.addActionListener(this);
Term.addActionListener(this);
Payment.addActionListener(this);
CalculateButton.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
Object command = e.getSource();
if (command == ExitButton) {
System.exit(0);
}
else if (command == Loan7) {
calcLoan(terms[0], rates[0]);
}
else if (command == Loan15) {
calcLoan(terms[1], rates[1]);
}
else if (command == Loan30) {
calcLoan(terms[2], rates[2]);
}
else if (command == CalculateButton) {
double terms = 0;
double rates = 0;
try {
terms = Double.parseDouble(Term.getText());
rates = Double.parseDouble(InterestRate.getText());
}
catch (Exception ex) {
LoanPayments.setText("Invalid term or rate Amount");
return;
}
calcLoan(terms, rates);
}
else if (command == ClearButton) {
mortgageAmount.setText("");
Payment.setText("");
InterestRate.setText("");
Term.setText("");
LoanPayments.setText("");
}
}
private void calcLoan(double terms, double rates) {
Term.setText(String.valueOf(terms));
InterestRate.setText(String.valueOf(rates));
double amount = 0;
try {
amount = Double.parseDouble(mortgageAmount.getText());
}
catch (Exception ex) {
LoanPayments.setText("Invalid mortgage Amount");
return;
}
double interestRate = rates;
//interest rate here
double intRate = (interestRate / 100) / 12;
//Laon term calculaton for month
int months = (int) terms * 12;
// coverts terms to month
double rate = (intRate / 12);
//interest rate to monthly interest here
double payment = amount * intRate
/ (1 - (Math.pow(1 / (1 + intRate), months)));
//Monthly payments here
double remainingPrincipal = amount;
//Balance
double MonthlyInterest = 0;
//interest payment
double MonthlyAmt = 0;
//loan payment
//formats for output to table
NumberFormat CurrencyFormatter = NumberFormat.getCurrencyInstance();
Payment.setText(CurrencyFormatter.format(payment));
LoanPayments.setText("Month\tPrincipal\tInterest\tEnding Balance\n");
//months
int currentMonth = 0;
while (currentMonth < months) {
//details for mortgage text
MonthlyInterest = (remainingPrincipal * intRate);
//Payment Interest
MonthlyAmt = (payment - MonthlyInterest);
//Monthly Payment towards loan balance
remainingPrincipal = (remainingPrincipal - MonthlyAmt);
//loan Balance remaining
LoanPayments.append((++currentMonth) + "\t"
+ CurrencyFormatter.format(MonthlyAmt) + "\t"
+ CurrencyFormatter.format(MonthlyInterest) + "\t"
+ CurrencyFormatter.format(remainingPrincipal) + "\n");
GraphArea.append("" + remainingPrincipal);
}
}
public void paint(Graphics g)
{
double width = 900.00;
int height= 400;
double x=1.0;
double y=0.0;
int counter = 0;
double xincrement = (width/(dblTerm*12));
double yincrement = height/dblmortgageAmount;
g.drawString("Payments", 65, 10);
while (counter <= 10) {
x = x + xincrement;
g.drawString(Integer.toString((int)((((dblLoanDuration*12)/10)*counter))), (int)((width/10)*counter)+55, 20);
counter++;
drawn = true;
}
double amount=dblLoanAmount;
double payment=amount/12;
g.drawString("Amount", 0, 20);
while (y < height) {
y = y + (height/12);
g.drawString(paymentFormat.format(amount), 0, (int)y);
amount = amount-payment;
}
public static void main(String[] args) {
Calculator frame = new Calculator();
}
}
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