Lab #16 (Exercise 17-1)

Implement an event listener as a separate class

Due Date: Thursday of Week 5
10 points

In this lab, you'll create

Open the FutureValueApp file.

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

public class FutureValueApp
{
    public static void main(String[] args)
    {
        JFrame frame = new FutureValueFrame();
        frame.setVisible(true);
    }
}

class FutureValueFrame extends JFrame
{
    public FutureValueFrame()
    {
        setTitle("Future Value Calculator");
        centerWindow(this);
        setSize(267, 200);
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new FutureValuePanel();
        this.add(panel);
    }

    private void centerWindow(Window w)
    {
        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension d = tk.getScreenSize();
        setLocation((d.width-w.getWidth())/2, (d.height-w.getHeight())/2);
    }
}

class FutureValuePanel extends JPanel implements ActionListener
{
    private JTextField  paymentTextField,
                        rateTextField,
                        yearsTextField,
                        futureValueTextField;
    private JLabel      paymentLabel,
                        rateLabel,
                        yearsLabel,
                        futureValueLabel;
    private JButton     calculateButton,
                        exitButton;

    public FutureValuePanel()
    {
        // display panel
        JPanel displayPanel = new JPanel();
        displayPanel.setLayout(new FlowLayout(FlowLayout.RIGHT));

        // payment label
        paymentLabel = new JLabel("Monthly Payment:");
        displayPanel.add(paymentLabel);

        // payment text field
        paymentTextField = new JTextField(10);
        displayPanel.add(paymentTextField);

        // rate label
        rateLabel = new JLabel("Yearly Interest Rate:");
        displayPanel.add(rateLabel);

        // rate text field
        rateTextField = new JTextField(10);
        displayPanel.add(rateTextField);

        // years label
        yearsLabel = new JLabel("Number of Years:");
        displayPanel.add(yearsLabel);

        // years text field
        yearsTextField = new JTextField(10);
        displayPanel.add(yearsTextField);

        // future value label
        futureValueLabel = new JLabel("Future Value:");
        displayPanel.add(futureValueLabel);

        // future value text field
        futureValueTextField = new JTextField(10);
        futureValueTextField.setEditable(false);
        futureValueTextField.setFocusable(false);
        displayPanel.add(futureValueTextField);

        // button panel
        JPanel buttonPanel = new JPanel();
        buttonPanel.setLayout(new FlowLayout(FlowLayout.RIGHT));

        // calculate button
        calculateButton = new JButton("Calculate");
        calculateButton.addActionListener(this);
        buttonPanel.add(calculateButton);

        // exit button
        exitButton = new JButton("Exit");
        exitButton.addActionListener(this);
        buttonPanel.add(exitButton);

        // add panels to main panel
        this.setLayout(new BorderLayout());
        this.add(displayPanel, BorderLayout.CENTER);
        this.add(buttonPanel, BorderLayout.SOUTH);
    }

    public void actionPerformed(ActionEvent e)
    {
        Object source = e.getSource();
        if (source == exitButton)
            System.exit(0);
        else if (source == calculateButton)
        {
            double payment = Double.parseDouble(paymentTextField.getText());
            double rate = Double.parseDouble(rateTextField.getText());
            int years = Integer.parseInt(yearsTextField.getText());
            double futureValue = FinancialCalculations.calculateFutureValue(
                payment, rate, years);
            NumberFormat currency = NumberFormat.getCurrencyInstance();
            futureValueTextField.setText(currency.format(futureValue));
        }
    }
}

Review the code for this application to see that the ActionEvent listener for the Calculate and Exit buttons are implemented by the FutureValuePanel class.

Run the application to refresh your memory on how it works.

Modify the application so that the ActionEvent Listener for the Calculate and Exit buttons is implemented in a separate class rather than by the FutureValuePanel class.

Compile the application, and test it to be sure it still works correctly.

Include in your program the following comments:

Name of program
Team's name with all the names of the members (e.g. Team A: John Doe, Jane Smith, etc.)
Current Date
Computer system and compiler you are using
Brief description of the program

Compile and run the Java program.

Take a screen capture by hitting simultaneously the keys Alt and Print Screen (Prt Sc) of the output results (console) and paste it in MS Paint. Save it as a gif file.

When you are ready, upload the java program and the gif file by clicking the link below:

Upload Lab

I cannot grade if I don't get the files and receive your email.