Re: how to exit gracefully

From:
Eric Sosman <esosman@ieee-dot-org.invalid>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 16 Dec 2010 12:01:04 -0500
Message-ID:
<iedgmu$9nt$1@news.eternal-september.org>
On 12/16/2010 11:01 AM, mark jason wrote:

hi,
I have an application that expects a certain number of command line
arguments.I need to check the number of command line args and if
sufficient number of arguments are not provided ,would like to print
the error message and exit.I have heard that using
System.exit(somenumber) is frowned upon.Which is the best practice?
regards
mark.

class MyApp{
     ....
     public static void main(String[] args){
         if (args.length< 4){
             System.out.println("Usage: java MyApp fname sname
citycode statecode");
             System.exit(1);
         }
         String firstname = args[0];
         String surname = args[1];
         String cityCode = args[2];
         String stateCode = args[3];
         new MyApp().process(firstname, surname, cityCode, stateCode);
         ...
     }
}


     Since you're detecting the problem in main(), before you've
done anything like set up database connections or launch forty-two
worker threads, you could just return. My preference, though, would
be to throw an exception: It'll make more noise, and be more likely
to draw someone's attention.

--
Eric Sosman
esosman@ieee-dot-org.invalid

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