Try

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

public class LottoEvent implements ItemListener, ActionListener,
Runnable {

public void run() {}

public void actionPerformed (ActionEvent evt) {}

public void itemStateChanged(ItemEvent item) {}

}

That error is telling you that you are implementing an interface (or in
this case interfaces). Interfaces enforce certain methods, so when you
implement the interface you have to implement the methods of the
interface. That is why you're getting the errors.

See:

http://java.sun.com/j2se/1.5.0/docs/api/java/awt/event/ItemListener.html

http://java.sun.com/j2se/1.5.0/docs/api/java/awt/event/ActionListener.htm
l

http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Runnable.html

BTW the code you posted does not give the error you claimed, it says
this:

C:\JAVA\LottoEvent.java:4: LottoEvent should be declared abstract; it
does not define run() in LottoEvent
public class LottoEvent implements ItemListener, ActionListener,
Runnable {

I take it that was a typo or mistake ;)

This message sounds misleading. I think what it means is you failed to
provide a suitable itemStateChanged method to implement ItemListener.

If you have a class which is implemented from an Interface. You have to
add all the implemented methods.