1    package javassist.sample.vector; 
2     
3    public class Sample extends java.util.Vector { 
4        public void add(X e) { 
5            super.addElement(e); 
6        } 
7     
8        public X at(int i) { 
9            return (X) super.elementAt(i); 
10       } 
11   } 
12    
13   class X { 
14   } 
15