请帮我看看那里错了 菜鸟

import java.awt.*;
import java.awt.event.*;
public class drowline{
Frame f=new Frame("画线");
f.addWindowListener(new MyWindowListener());
public static void main (String [] args){
   new drowline().init();
}
public void init(){
f.setSize(300,300);
f.setVisible(true);
f.addMouseListener( new MouseAdapter()
{int x;
 int y;
 public void mousePressed(MouseEvent e){
  x=e.getX();
  y=e.getY();
 }
 public void mouseReleased (MouseEvent e){
  f.getGraphics().setColor(Color.blue);
  f.getGraphics().drawLine(x,y,e.getX(),e.getY());
 
 }

});
}
}
class MyWindowListener implements WindowListener {
public void windowClosing(WindowEvent e){
e.getWindow().setVisible(false);
System.exit(0);

}
public void windowActivated(WindowEvent e){
}
public void windowClosed(WindowEvent e){
}
public void windowDeactivated(WindowEvent e){
}
public void windowDeiconified(WindowEvent e){
}
public void windowIconified(WindowEvent e){
}
public void windowOpened(WindowEvent e){
}

}
E:\ysheny\study\java\javap\drowline.java:5: <identifier> expected
                f.addWindowListener(new MyWindowListener());
                                   ^
1 error谢谢 我是刚接触java