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Thread: Error in Lectures notes(please help)

  1. #1
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    Default Error in Lectures notes(please help)

    Hi this is the code i downloaded off my lectures example folder im getting an error that says "Exception in thread "main" java.lang.NoSuchMethodError: main" but there is no main class can anyone help


    import javax.swing.*;
     
    import java.awt.Dimension;
    import java.awt.BorderLayout;
     
    import java.awt.event.ActionListener;
    import java.awt.event.ActionEvent;
    import java.awt.event.WindowEvent;
    import java.awt.event.WindowListener;
     
    public class WindowEventDemo extends JApplet implements WindowListener,ActionListener
    {
        JTextArea display;
        JFrame window;
        JButton b1, b2;
        static final String SHOW = "show";
        static final String CLEAR = "clear";
        final static String newline = "\n";
     
     
        public void init() {
            b1 = new JButton("Click to bring up a window.");
            b1.setActionCommand(SHOW);
            b1.addActionListener(this);
     
            b2 = new JButton("Click to clear the display.");
            b2.setActionCommand(CLEAR);
            b2.addActionListener(this);
     
            display = new JTextArea();
            display.setEditable(false);
            JScrollPane scrollPane = new JScrollPane(display);
            scrollPane.setPreferredSize(new Dimension(200, 75));
     
            JPanel contentPane = new JPanel();
            contentPane.setLayout(new BorderLayout());
            contentPane.add(b1, BorderLayout.NORTH);
            contentPane.add(scrollPane, BorderLayout.CENTER);
            contentPane.add(b2, BorderLayout.SOUTH);
            setContentPane(contentPane);
     
            //Create but don't show window.
            window = new JFrame("Window Event Window");
            window.addWindowListener(this);
            JLabel l = new JLabel("The applet listens to this window"
                                + " for window events.");
            window.getContentPane().add(l, BorderLayout.CENTER);
            window.pack();
        }
     
        public void stop() {
            window.setVisible(false);
        }
     
        public void windowClosing(WindowEvent e) {
            window.setVisible(false);
            displayMessage("Window closing", e);
        }
     
        public void windowClosed(WindowEvent e) {
            displayMessage("Window closed", e);
        }
     
        public void windowOpened(WindowEvent e) {
            displayMessage("Window opened", e);
        }
     
        public void windowIconified(WindowEvent e) {
            displayMessage("Window iconified", e);
        }
     
        public void windowDeiconified(WindowEvent e) {
            displayMessage("Window deiconified", e);
        }
     
        public void windowActivated(WindowEvent e) {
            displayMessage("Window activated", e);
        }
     
        public void windowDeactivated(WindowEvent e) {
            displayMessage("Window deactivated", e);
        }
     
        public void displayMessage(String prefix, WindowEvent e) {
            display.append(prefix
                           + ": "
                           + e.getWindow()
                           + newline);
        }
     
        public void actionPerformed(ActionEvent e) {
            if (e.getActionCommand() == SHOW) {
                window.pack();
                window.setVisible(true);
            } else {
                display.setText("");
            }
        }
    }


  2. #2
    Administrator copeg's Avatar
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    Default Re: Error in Lectures notes(please help)

    "Exception in thread "main" java.lang.NoSuchMethodError: main" but there is no main class can anyone help
    The jvm cannot find the main method, not a main class. However, given this class extends a JApplet, it should be run as an applet not an application eg you are better off trying to run it through Appletviewer or some alternative to view applets

  3. The Following User Says Thank You to copeg For This Useful Post:

    Pulse_Irl (October 12th, 2010)