Re: What's java equivalent of C's argv[ 0 ]?

From:

joseph_daniel_zukiger@yahoo.com

Newsgroups:

comp.lang.java.programmer

Date:

25 Apr 2006 18:25:48 -0700

Message-ID:

<1146014748.340325.253370@i40g2000cwc.googlegroups.com>

joseph_daniel_zukiger@yahoo.com wrote:

Patricia Shanahan wrote:

joseph_daniel_zukiger@yahoo.com wrote:

I thought I knew this once, but maybe I was just fooling myself.

this.getClass().getName() doesn't work from static methods, so it
doesn't work from main().

[...]

Here's one way:

public class TestNaming {
   public static void main(String[] args) {
     System.out.println(new NameGetter().getName());
   }
   static class NameGetter{
     String getName(){
       return getClass().getDeclaringClass().getName();
     }
   }
}

This is not strictly a replacement for argv[0]. It only tells you the
name of the class in which the NameGetter is declared. For example, if I
called that main() method in another program, it would still report
"TestNaming". Each class for which you want to be able to get the name
from static contexts must declare its own NameGetter as a static nested
class.

It looks like it does the job for what I had in mind, if only what I
had in mind would have worked.

The problems with setting the Mac OS X application menu name from
within Java code aside, I took Patricia Shanahan's suggestion a step
further and used static initialization to salt the fully qualified
class name away in a class variable without having to mention it in
main(). For the archives:

public class AMainClass
{
    // Other things in the main class here ...

    public static void main( final String[] args )
    {
        // ...
        System.out.println( "main Class name: " + AMainClass.mainClassName );
    }

    /**
     * argv[ 0 ]
     * Courtesy of Patricia Shanahan on comp.lang.java.programmer:
     */
    private static class NameGetter
    { public String getName()
        { // Returns the fully qualified class name.
            return getClass().getDeclaringClass().getName();
        }
    }
    //
    public static final String mainClassName = new NameGetter().getName();

}