Re: doubt in public static void main

From:

Robert Klemme <shortcutter@googlemail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 02 Aug 2006 16:08:29 +0200

Message-ID:

<4jbputF7a66jU1@individual.net>

sarathy wrote:

Hi all,
I have doubt in the signature of the main method.

Why public?
Any how only JVM is going to invoke it. No one is going to
call main from other classes/packages. Then a private will do for this.

Why is no one going to invoke main other than the VM? You could well do
that for testing purposes etc. And a public method has the added
documentation advantage that everybody immediately sees that it's called
from "outside". Maybe there's also some security manager issue.

Why static?
Why was the main method restricted from accessing
non-static instance variables/methods.

Initially there is no object hence no instance to invoke the method on
if it was non static. And how should the VM know which of several
defined constructors it should use?

Why void?
Normally any main method MUST return a value so that it's
exit value is can be used by other programs. Why is it void here?

I speculate it's because not all OS provide a numeric exit status for
processes or handle it the same way.

Regards

robert