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Re: Eclipse - NoSuchMethodError: main

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On 03/23/2012 06:36 AM, William Colls wrote:
> On 03/21/2012 08:46 PM, Eric Sosman wrote:
>> On 3/21/2012 10:17 AM, William Colls wrote:
>>> I think this is really an Eclipse problem.
>>>
>>> When I try to run my program, I get the error message
>>>
>>> NoSuchMethodFound: main
>>>
>>> The file does in fact contain a main method, declared as public static
>>> void, with no arguments.
>>>
>>> I suspect that Eclipse is looking in the wrong place for the method, but
>>> in every place that I can find in the various configurations, the file
>>> that I am running is identified as the file containing containing the
>>> main() method.
>>>
>>> Any suggestions as to where further to look will greatfully received.
>>
>> Others have explained that "main" must have a parameter list
>> consisting of exactly one String array. For completeness' sake,
>> it's *possible* to have a "main" with some other signature; as with
>> any other method, you can overload "main" as you wish:
>>
>> public static void main(String[] args) { ... }
>> public static int main() { return 42; }
>> public static double main(String justOneArg) {
>> return Double.parseDouble(justOneArg);
>> }
>> ...
>>
>> However, the particular "main" that Java (not just Eclipse) looks
>> for when starting execution is the one and only "main" that has the
>> first form above. (You can write "String... args" instead of
>> "String[] args" if you like, but it's the same thing. Java starts
>> with the "main" whose parameter list is one String array, however
>> you happen to express it.)
>>
>> Only the type of the formal parameter matters; the actual name
>> is irrelevant. When the arguments aren't used, my own personal
>> practice is to write
>>
>> public static void main(String[] unused) { ... }
>>
>> The only drawback is that code-policing tools sometimes insist
>> that I write Javadoc comments for the "unused" parameter ;-)
>>
> Thanks to all who replied. I changed the the signature to
>
> public static void(String[] args)
>
> but it made no difference - same problem.

That would fail to compile.

Please prepare an SSCCE for us.
http://sscce.org/

> I made the assumption that it was/is an Eclipse configuration issue, based on
> the fact that When I first started with Java, I was using the Netbeans IDE,
> and the main() worked perfectly well there, but I would get the
> NoSuchMethodError if project setup page didn't point to the correct file.

What happens when you invoke it via "java" on the command line?

> I have side-stepped the problem by creating a small class that does have a
> main method, imports the class I have defined and am building, and then

This makes no sense at all. Something there is you have not told us, mmm.

> instansiates an object form it, and invokes the methods I need to test. Better
> solution, as it more closely the real world use of the work I am doing.

-- 
Lew
Honi soit qui mal y pense.
http://upload.wikimedia.org/wikipedia/commons/c/cf/Friz.jpg

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Eclipse - NoSuchMethodError: main William Colls <william.colls@rogers.com> - 2012-03-21 10:17 -0400
  Re: Eclipse - NoSuchMethodError: main Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2012-03-21 16:41 +0200
  Re: Eclipse - NoSuchMethodError: main markspace <-@.> - 2012-03-21 08:18 -0700
  Re: Eclipse - NoSuchMethodError: main Lew <lewbloch@gmail.com> - 2012-03-21 13:41 -0700
  Re: Eclipse - NoSuchMethodError: main Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-03-21 20:46 -0400
    Re: Eclipse - NoSuchMethodError: main Arne Vajhøj <arne@vajhoej.dk> - 2012-03-21 21:00 -0400
      Re: Eclipse - NoSuchMethodError: main BGB <cr88192@hotmail.com> - 2012-03-21 21:59 -0700
        Re: Eclipse - NoSuchMethodError: main Patricia Shanahan <pats@acm.org> - 2012-03-22 03:13 -0700
          Re: Eclipse - NoSuchMethodError: main Arne Vajhøj <arne@vajhoej.dk> - 2012-03-22 21:46 -0400
            Re: Eclipse - NoSuchMethodError: main Lew <lewbloch@gmail.com> - 2012-03-22 18:49 -0700
              Re: Eclipse - NoSuchMethodError: main Gene Wirchenko <genew@ocis.net> - 2012-03-22 22:17 -0700
    Re: Eclipse - NoSuchMethodError: main William Colls <william.colls@rogers.com> - 2012-03-23 09:36 -0400
      Re: Eclipse - NoSuchMethodError: main Lew <noone@lewscanon.com> - 2012-03-23 07:51 -0700
        Re: Eclipse - NoSuchMethodError: main Patricia Shanahan <pats@acm.org> - 2012-03-23 08:49 -0700
  Re: Eclipse - NoSuchMethodError: main Jan Burse <janburse@fastmail.fm> - 2012-03-23 18:05 +0100

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