Abstract error that i don't understand.

[DidierD]

Hey,

So im getting an error that says that my class is not abstract and can't overun the abstract method im trying to use ( Action Performed ) well if anyone can figure out the error or give some input on this the files are linked below:

the error is:

Didier$ javac *.java
GameInterface.java:7: GameInterface is not abstract and does not override abstract method actionPerformed(java.awt.event.ActionEvent) in java.awt.event.ActionListener
public class GameInterface extends JFrame implements ActionListener{
^
1 error

The file that has the error:

GameInterface.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.border.*;
import javax.swing.JComponent.*;

public class GameInterface extends JFrame implements ActionListener{

	GridForGame gridForGame = new GridForGame();

	public GameInterface(){
		super("Bubble Breaker - Java Version. By Gary Tremarco");
		buildGUI();
		setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
		pack();
		setVisible(true);
		setResizable(false);
	}
	
	private void buildGUI(){
		JPanel main = new JPanel(new BorderLayout());
		add(main, BorderLayout.CENTER);
		
		JPanel menu = new JPanel();
		menu.setLayout(new BoxLayout(menu, BoxLayout.Y_AXIS));
		menu.setPreferredSize(new Dimension(150,300));
		Dimension buttonSize = new Dimension(120,40);
		
		addButton("8 x 8 Grid", "small", buttonSize, menu);
		addButton("12 x 12 Grid", "medium", buttonSize, menu);
		addButton("16 x 16 Grid", "large", buttonSize, menu);
		addButton("How To Play", "howToPlay", buttonSize, menu);
		addButton("Options", "options", buttonSize, menu);
		addButton("Quit", "quitGame", buttonSize, menu);
		
		menu.setBorder(new TitledBorder(new EtchedBorder(4, Color.blue, Color.black), "Menu"));
		JPanel buttons = new JPanel(new GridLayout(1,1));
		buttons.add(menu);
		
		main.add(buttons, BorderLayout.EAST);
		main.add(gridForGame, BorderLayout.CENTER);
		
	}
	
	public void addButton(String label, String command, Dimension size, JPanel panel){
		
		JButton button = new JButton(label);
		button.setPreferredSize(size);
		button.setMaximumSize(size);
		Dimension seperatorSize = new Dimension(0,5);
		button.setAlignmentX(CENTER_ALIGNMENT);
		button.addActionListener(this);
		button.setActionCommand(command);
		panel.add(Box.createRigidArea(seperatorSize));
		panel.add(button);
	}
	
	public void ActionPerformed(ActionEvent ae){
		
		String command = ae.getActionCommand();
		if (command == "small"){
			gridForGame.small();
		}
		
		if (command == "medium"){
			gridForGame.medium();
		}
		
		if (command == "large"){
			gridForGame.large();
		}
		
		if(command.equals("howToPlay")){
			// check source code for URL that goes here
		}
		
		if(command.equals("options")){
			// check source image for code that goes here
		}
		
		if(command == "quitGame"){
			int selectedValue = JOptionPane.showConfirmDialog(null, "If Your Quit The Game All Data Will Be Lost" +
				"\n" + "Are You Sure You Want To Quit?", "Attention", JOptionPane.YES_NO_OPTION);
			// Might be issues above due to splitting brackets onto lines
			
			if(selectedValue == JOptionPane.NO_OPTION)
				return;
			
			else System.exit(0);
			
		}
	}
	
	public static void main( String args[]){
		GameInterface i = new GameInterface();
		i.addWindowListener(new WindowAltering());
	}
	
	static class WindowAltering extends WindowAdapter{
		public void windowClosing(WindowEvent e ){
			int selectedValue = JOptionPane.showConfirmDialog(null, "Closing This Window Will End the Game." +
				"\n" + "Click Yes To Exit", "Exit Bubble Breaker Game?", JOptionPane.YES_NO_OPTION);
			if(selectedValue == JOptionPane.NO_OPTION)
				return;
			
			else System.exit(0);
		}
	}
}

and its accompanied file:

http://www.didierd.co.uk/bubble/GridForGame.java

or if you don't feel comfortable downloading the files, i can put the source anywhere else if you like?

Thank you for any help!