CSV Table

Hey guys,



Found this online, and as a beginner i have really trouble reading the code and understanding what really is happening ..

Do someone mind like explaining this code in the details and step they occur?? any help would be much appreciated..
thank you

 import java.io.*;
 import java.net.URL;
 import java.util.Scanner;
 import javax.swing.*;
 import javax.swing.table.DefaultTableCellRenderer;
 import javax.swing.table.DefaultTableModel;

 public class CSVTable extends JFrame {
    JTable table;
    DefaultTableModel model;
    JButton closeButton, webButton;
  /**
   * Takes data from a CSV file and places it into a table for display.
   * @param source - a reference to the file where the CSV data is located.
   */
  public CSVTable(String title, String source) {
    super(title);
    table = new JTable();
    JScrollPane scroll = new JScrollPane(table);
    String[] colNames = { "LastName", "FirstName", "Email Address", "Dept."};
    model = new DefaultTableModel(colNames, 0);
    InputStream is;
    try {
        if(source.indexOf("http")==0) {
            URL facultyURL = new URL(source);
            is = facultyURL.openStream();
        }
        else { //local file?
            File f = new File(source);
            is = new FileInputStream(f);
        }
        insertData(is);
        //table.getColumnModel().getColumn(0).setCellRende
rer(new CustomCellRenderer());
    }
    catch(IOException ioe) {
        JOptionPane.showMessageDialog(this, ioe, "Error reading data", JOptionPane.ERROR_MESSAGE);
    }

    JPanel buttonPanel = new JPanel();
    closeButton = new JButton("Close");
    webButton = new JButton("Proctinator.com");
    buttonPanel.add(closeButton);
    buttonPanel.add(new JLabel("   You can download this file from our site: "));
    buttonPanel.add(webButton);

    JPanel notesPanel = new JPanel();
    JLabel note1 = new JLabel(" Make sure that your list is formatted exactly as shown below, including the *markers between categories ");
    JLabel note2 = new JLabel(" Be sure to place each faculty member into the correct category: *Teacher, *Subs, *TeacherAids, *TeacherAssistants ");
    JLabel note3 = new JLabel(" Note that the your faculty list must be a plain text file:  Export to either CSV or tab delimited format.");
    BoxLayout layout = new BoxLayout(notesPanel, BoxLayout.Y_AXIS);
    notesPanel.setLayout(layout);
    notesPanel.add(note1);
    notesPanel.add(note2);
    notesPanel.add(note3);       
    getContentPane().add(notesPanel, BorderLayout.NORTH);
    getContentPane().add(scroll, BorderLayout.CENTER);
    getContentPane().add(buttonPanel, BorderLayout.SOUTH);
    pack();
}

/**
 * Places the data from the specified stream into this table for display.  The data from the file must be in CSV format
 * @param is - an input stream which could be from a file or a network connection or URL.
 */
void insertData(InputStream is) {
    Scanner scan = new Scanner(is);
    String[] array;
    while (scan.hasNextLine()) {
        String line = scan.nextLine();
        if(line.indexOf(",")>-1)
            array = line.split(",");
        else
            array = line.split("\t");
        Object[] data = new Object[array.length];
        for (int i = 0; i < array.length; i++)
            data[i] = array[i];

        model.addRow(data);
    }
    table.setModel(model);
} 

public static void main(String args[]) {
    CSVTable frame = new CSVTable("Faculty List Example","http://proctinator.com/help/faculty.csv");
    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOS
E);
}

}