Exception in thread "main" java.lang.NoSuchMethodError: main

Question

when i try to compile this:

public class Risk
{
}
class territory 
{

    public static void main (String[]arg) 
    {
        System.out.println ("hi") ; 
    } 
}

I get this error message:

Exception in thread "main" java.lang.NoSuchMethodError: main

whats going wrong here?

Answer 1

What class are you trying to run? If you're using the class territory, that will work. Risk has no main method, though.

Answer 2

The class containing the main() function must be public, and you may only define one public class per file. You'll want to have two separate files Risk.java and Territory.java.

Risk.java:

public class Risk {
}

Territory.java:

public class Territory 
{

    public static void main (String[]arg) 
    {
        System.out.println ("hi") ; 
    } 
}

EDIT: It turns out this isn't true - I was able to run your initial code with the following command line:

java territory

But my earlier comments point to the best practice for a real app, such as a Risk game.

Answer 3

Could it just be a spacing issue? Your original post shows no space between the ']' and 'arg'.

Try this:

public static void main (String[] arg) 

or, if that still doesn't work:

public static void main (String arg[]) 

Answer 4

What the answer wound up being was that the class i run must contain main or else it won't work. i'm posting this because, though other answers give roughly the same information, they don't make it explicit.