帮我运行下看看 这是个么错误 就一个错误了 我是看不懂这个错误说的么意思
import java.awt.*;
import java.awt.event.*;
public class MenuExample extends FrameimplementsItemListener,ActionListener{
TextField tf;
public MenuExample(){
super("Menu Example");
setSize(300,200);
}
public void init() {
MenuBar mb = new MenuBar();
setMenuBar(mb);
Menu m1 = new Menu("File");
m1.add(new MenuItem("open..."));
mi1.setEnabled(false);
m1.add(mi1);
m1.add("close");
m1.addSeparator();
m1.add("Exit");
m1.addActionListener(this);
mb.add(m1);
Menu ms = new Menu("Option");
ms.add("Font...");
Menu ms = new Menu("Color...");
ms.add("Foreground");
ms.add("Background");
ms.addActionListener(this);
m2.add(ms);
m2.addSeparator();
CheckboxMenuItem cm = new CheckboxMenuItem("Always On Top");
cm.addItemListener(this);
m2.add(m2);
Menu h = new Menu("Help");
h.add("about...");
h.addActionListener(this);
mb.setHelpMenu(h);
tf = new TextField();
add("south",tf);
}
public static void main (String [] args){
MenuExample me = new MenuExample();
me.init();
me.setVisible(true);
}
public void itemStateChanged(ItemEvent e){
tf.setText("ItemStateChanged");
}
public void actionperformed(ActionEvent e){
tf.setText(e.getActionCommand());
if(e.getActionCommand()=="Exit"){
System.exit(0);
}
}
}
}