I was told that the variable accessed inside a anonymous inner class
needs to be static.
However the followign code from Thinking in java 3 works fine.
Why?

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

public class Button2b extends JApplet {
 private JButton
   b1 = new JButton("Button 1"),
   b2 = new JButton("Button 2");
 private JTextField txt = new JTextField(10);
 private ActionListener bl = new ActionListener() {
   public void actionPerformed(ActionEvent e) {
     String name = ((JButton)e.getSource()).getText();
     txt.setText(name);          ------question?  the txt is not final
but no complain from compiler
   }
 };
 public void init() {
   b1.addActionListener(bl);
   b2.addActionListener(bl);
   Container cp = getContentPane();
   cp.setLayout(new FlowLayout());
   cp.add(b1);
   cp.add(b2);
   cp.add(txt);
 }
 public static void main(String[] args) {
   Console.run(new Button2b(), 200, 75);
 }
} ///:~