Question about duplicate var declaration....

Question

the ff. code will compile and run... my question is there's a duplicate var declaration
(s var as a String type)...
Big Q: "Why the compiler didnt complain about it?"
it should be "duplicate var declaration" sort of thing......
public class Bits {
     public static void main(String args[]){
              new Bits();
    public Bits(){
         f1();
    private String s; // class var declaration, var name is "s"
    private void f1(){
       // another var declaration name "s", why the compiler dont complain about this!?!
         String s=new String("Hello World!");
         f2();
    private void f2(){
    // does this var "s" refers to the class var?
         System.out.println ("s: "+s); // the output is null
}Thanks!

Answer 1

Big Q: "Why the compiler didnt complain about it?"
it should be "duplicate var declaration" sort of
thing......Bcos one is a local variable and the other is an instance variable. They arent duplicates.
> private String s; // class var declaration, var name is "s"
>
private void f1(){
// another var declaration name "s", why the compiler dont complain about >this!?!
     String s=new String("Hello World!"); As i said b4, this is a local variable. Within the scope of this method, this variable hides the instance var, 's' , to access which, u will have to use this.s
>
private void f2(){
// does this var "s" refers to the class var?Yes.
System.out.println ("s: "+s); // the output is null//that's bcos u havent initialized it anywhere. Local variable have to be compulsorily initialized. Instance variables are initialized to null (if they are Object references)
ram.