Can someone explain to me what is this code doing?

Question

(I'm not asking why is the code not working, I'm asking what is it doing)

https://code.sololearn.com/ciHUxd1FOxv5/?ref=app

Answer 1

if you comment out the last 2 lines (that are out of the class) it will print "Hello World!"

the last 2 lines are out of a class, this is incorrect java syntax and makes the compiler fail.

e.g. with the offending lines commented out:
public class Program
{
public static void main(String[] args) {
System.out.println("Hello World!");
}
}
//Program A = new Program;
//A.main;

Answer 2

That's because I thought we can create objects of a class after defining it... My bad... 😂

Answer 3

In sololearn playground you can define more than one class that call each other, eg this way:
https://code.sololearn.com/cM3lFGUyMfTY/?ref=app

Answer 4

The main method is static, so it doesn't an object to run.