Question 21 :
What if I write static public void instead of public static void?
Program compiles and runs properly.
Question 22 :
What if I do not provide the String array as the argument to the method?
Program compiles but throws a runtime error "NoSuchMethodError".
Question 23 :
What is the first argument of the String array in main method?
The String array is empty. It does not have any element. This is unlike C/C++ where the first element by default is the program name.
Question 24 :
If I do not provide any arguments on the command line, then the String array of Main method will be empty or null?
It is empty. But not null.
Question 25 :
How can one prove that the array is not null but empty using one line of code?
Print args.length. It will print 0. That means it is empty. But if it would have been null then it would have thrown a NullPointerException on attempting to print args.length.