What is the difference between args and argh and argv in Java?

Question

While practicing some questions on hackerrank, some of the solutions had argh instead of args (which I have used mostly). Also, I got to know that there is another such argument that can be passed to main() function and that is argv. Thus in all there are three different arguments that exist:

args

argh

argv

Could you please tell me the difference between all three and how and when to use them?

And here is the code:

class Solution{
public static void main(String []argh){
    Scanner in = new Scanner(System.in);
    int n = in.nextInt();
    for(int i = 0; i < n; i++){
        String name = in.next();
        int phone = in.nextInt();
        // Write code here
    }
    while(in.hasNext()){
        String s = in.next();
        // Write code here
    }
    in.close();
  }
}

Please note that I am not asking for the solution to the above question. I have already solved it and made a successful submission but what I wanted to know was what difference would it make by adding argh instead of args?

thanks in advance!

Answer 1

Java function signatures are validated based on their return and arguments types, but never check for the name of the arguments. This means that

public static void main(String... parameters) { /* [...] */ }

is a valid main function.

It also means that you don't have to use the same argument names as an interface when implementing its functions, or as a class you extend when overloading its functions.