Thread: GUI error: is not abstract and does not override abstract method

Im trying to get a simple GUI working.

Firstly here is a brief description of the program:
Its just a small JFrame, with 1 button and an actionListener for when the button is pressed. The number of 'pushes' is updated and printed when the button is pressed.

I have a main class: PushCounter and another class: PushCounterPanel for which all the classes and methods are written for the JFrame

Heres the code:

package Chapter4;
 
// demonstrates a GUI and an event listener
import javax.swing.JFrame;
 
public class PushCounter {
 
    // creates the main program frame
    public static void main(String[] args) {
 
        JFrame frame = new JFrame("Push Counter");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        frame.getContentPane().add(new PushCounterPanel());
        frame.pack();
        frame.setVisible(true);
 
    }
}

package Chapter4;
 
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
// demonstrates a GUI and an event listener
public class PushCounterPanel extends JPanel {
 
    private int count;
    private JButton push;
    private JLabel label;
 
    // constructor: sets up the GUI
 
    public PushCounterPanel() {
        count = 0;
 
        push = new JButton("Push me!");
        push.addActionListener(new ButtonListener());
 
        label = new JLabel("Pushes: " + count);
 
        add(push);
        add(label);
 
        setPreferredSize(new Dimension(300, 40));
        setBackground(Color.cyan);
    }
 
    // represents a listener for button push (action) events
 
    private class ButtonListener implements ActionListener {
 
        // updates the counter and label when the button is pushed:
 
        public void actionperformed(ActionEvent event) {
            count++;
            label.setText("Pushes: " + count);
        }
    }
}

And the error:

PushCounterPanel.ButtonListener is not abstract and does not override abstract method
action performed (java.awt.ActionEvent) in java.awt.event.ActionListener

Its on line 33 (this line) :

private class ButtonListener implements ActionListener {

In which ButtonListener is red underlined



Any input appreciated

Should have posted this aswell: its what i get when i actually try to run it:

run:
Exception in thread "main" java.lang.ExceptionInInitializerError
at Chapter4.PushCounter.main(PushCounter.java:14)
Caused by: java.lang.RuntimeException: Uncompilable source code - Chapter4.PushCounterPanel.ButtonListener is not abstract and does not override abstract method actionPerformed(java.awt.event.ActionEvent) in java.awt.event.ActionListener
at Chapter4.PushCounterPanel.<clinit>(PushCounterPane l.java:33)
... 1 more
Java Result: 1

the method actionperformed should be

  public void actionPerformed(ActionEvent event) 
  {
     //Code not included
  }

Simple typo.

Oh yeah.

Thanks