public class ProgramAssignment5 extends JFrame{


	// Declare JFrame components to be used on GUI
    JButton btnReadFile, btnShowName, btnSort;

    // Declare output area
    static JTextArea jtaDisplay;

    // Declare an array of create Course(class) objects to manage up to 100 Courses
    private static payroll [] payroll = new payroll [100];

    // Declare a class variables(static)  to be used count for array
    private static int count = 0;

/***************************************************************************************/
    public ProgramAssignment5()
    {
        // Call constructor of superclass JFrame to title the frame
        super("CSC 120:  Final Program – Spring 2019 – Due last day of class(4/25) (before 11:55 pm)");

        // Construct a label for instructions to the user
        JLabel lblInstructions = new JLabel("Click on READ FILE to get course information,\n then click on SHOW MY COURSES");

        // Construct button objects
        btnReadFile = new JButton("READ FILE");
        btnShowPayroll = new JButton ("SHOW PAYROLL");
        btnSort = new JButton ("SORT BY COURSE PREFIX");

        // Construct a scrollable JTextArea
        JTextArea jtaDisplay = new JTextArea(10,30);
        JScrollPane scrollPane = new JScrollPane(jtaDisplay);

        // Make the text area uneditable
        jtaDisplay.setEditable(false);

        // Declare and construct panels for components
        JPanel pnlInstructions = new JPanel();
        JPanel pnlButtons = new JPanel();
        JPanel pnlDisplay = new JPanel();

        // Add event handlers to the buttons
        btnReadFile.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        // read file
                        jtaDisplay.setText("Reading File...");
                        readFile();
                        lblInstructions.setText("Click on SHOW MY COURSES");
                    }// End
                }
            );

        btnShowPayroll.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        // display formatted contacts in text area on GUI
                        jtaDisplay.setText("Payroll:\n\n");
                        lblInstructions.setText("Use Scroll Bars for more courses");
                        jtaDisplay.setText("Payroll");
                        for (int i = 0; i < count; i++)
                        {
                            jtaDisplay.append("\n" + Payroll [i]);
                        }

                    }
                }
            );


        btnSort.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        // sort by prefix
                        sortBy();  //call this method
                        // Message shown after sort is complete
                        jtaDisplay.setText("Courses Sorted by Course Prefix");
                        for (int i = 0; i < count; i++)
                        {
                            jtaDisplay.append("\n\n" + Payroll[i]);
                        }
                    }
                }
            );

        // Add instructions label to the instructions panel
        pnlInstructions.add(lblInstructions);

        // Add button components to the button panel
        pnlButtons.add(btnReadFile);
        pnlButtons.add(btnShowPayroll);
        pnlButtons.add(btnSort);

        // Add the scrollable text area to the display panel
        pnlDisplay.add(scrollPane);

        // Add the panels to the JFrame
        add(pnlInstructions, BorderLayout.NORTH);
        add(pnlButtons, BorderLayout.SOUTH);
        add(pnlDisplay, BorderLayout.CENTER);

        // Set the size of the JFrame
        setSize(550,300);

        // Center JFrame
        setLocationRelativeTo(null);

        // Make the JFrame Visible
        setVisible(true);

        //
    }// End JFrame constructor

/***************************************************************************************/

public static void main(String[] args) {
	}


public static void readFile()
{
    // Declare a Scanner object for input
	Scanner scannerLine = new Scanner("");

    //try-catch blocks
    try
    {
        // Use a text file named "courses.text" to create a Scanner object "input"
        Scanner input = new Scanner(new File("payroll.txt"));

    while (input.hasNext())
    {
        // Store the line as a String
        String stringLine = input.nextLine();
        // Use the String to create a new Scanner for just that one line
        scannerLine = new Scanner (stringLine);
        // Use a delimeter (",") which will separate each field on the line
        scannerLine.useDelimiter(",");

        /*Use following text file format:
         *  Arts & Sciences,Psychology,PSY,120,3,Introduction to Psychology,A,Fall,2017,An introduction to the field of Psychology
         *  read each token and use to instantiate an instance of the Course class (implemented in a separate file)
         *  and assign each object of Course into an element of a Course array*/
         payroll [count] = new Payroll
                (
                	scannerLine.nextInt(), // gets course ID from line
                	scannerLine.next(),    //gets department from line
                    scannerLine.next(),    //gets subject from line
                    scannerLine.next(),    //gets course prefix from line
                    scannerLine.nextInt(), //gets course number from line
                    scannerLine.nextInt(), //gets hours from line
                    scannerLine.next(),    //gets course title from line
                    scannerLine.next(),   //gets grade from line
                    scannerLine.next(),   //gets term from line
                    scannerLine.nextInt(),  //gets year from line
                    scannerLine.next(),  //gets course summary from line
         			scannerLine.next());   // gets instructor name
                count ++;
    }// End while
    }// End try block
    catch (IOException ioe)
    {
        JOptionPane.showMessageDialog(null,"File not found");
        // End program
        System.exit(0);
    }// End catch block
    finally
    {
        scannerLine.close();
        { // End finally block
        }
    }
}
}// End readFile