How pointers behave inside containers..

Hello.java

import java.util.*;
public class Hello{

     public static void main(String []args){
        System.out.println("Hello World");
        ArrayList<String> a1 = new ArrayList<String>();
        ArrayList<String> b1 = a1;
        b1.add("hello");
        b1.add("yo!");
        System.out.println(a1.toString());
     }
}