[Java] "type expected" ma non so perchè

[peppe79]

mi aiutate a capire cosa sbaglio?

import java.awt.*;
import java.awt.Font;
import java.awt.event.*;
import java.applet.Applet;

public class Mittelwert_GUI extends Applet{
implements WindowListener, ActionListener{
 Button b_berechne, b_loeschen;
 Font fnt_l_Titel, fnt_tf_Wert1, fnt_tf_Wert2, fnt_tf_Ergebnis, fnt_b_Berechne, fnt_b_Loeschen;

 public void init(){
  resize(400,200);
  ...
  // Buttons
  b_berechne  = new Button("Rechne Mittelwert");
  b_loeschen  = new Button("Loeschen");
  // GUI-Komponeneten
  ...
  b_berechne.setBounds(125,80,150,20);
  b_loeschen.setBounds(125,160,150,20);
  ...
  add(b_berechne);
  add(b_loeschen);
  // Font-Objekte
  ...
  fnt_b_Berechne = new Font("SansSerif", 1, 14);
  fnt_b_Loeschen = new Font("SansSerif", 1, 14);

  ...
  b_berechne.setFont(fnt_b_Berechne);
  b_loeschen.setFont(fnt_b_Loeschen);

  b_berechne.addActionListener(this);
  b_loeschen.addActionListener(this);
  addWindowListener(this);
 }
 public void start(){
  public void windowClosing(WindowEvent e){
   dispose();
   System.exit(0);
  }

  public void actionPerformed(ActionEvent e){
    if(e.getSource() == b_berechne){
     berechneClicked();
    }
    if(e.getSource() == b_loeschen){
     loeschenClicked();
    }
  }
 }
}
}