[gecode-users] Gecode/J - gist

[Guido Tack]

Hi.

Miroslava Plachá wrote:

> Hi,
> I uninstalled and reinstalled Gecode/J (the last release) and when  
> I try to run
> any given example (and see gist working) I get this error:
>
> C:\javagecode\druhy\Gist\src\examples\Options.java:16: cannot access
> org.gecode.gist.Gist
> bad class file: C:\Program Files\Java\jdk1.5.0_09\jre\lib\ext 
> \GecodeJ.jar(org/gecode/gist/Gist.class)
> class file has wrong version 50.0, should be 49.0
> Please remove or make sure it appears in the correct subdirectory  
> of the
> classpath.
> import org.gecode.gist.Gist;
>
> I didn't touch anything in Options.java (have a new project with  
> this class
> and one example).
> If I write my own program (just with org.gecode classes) it works  
> fine.
>
> What can be wrong and how can I fix it?

This is a bug in the Windows package that we only found recently.  
Apparently, stuff compiled with Java 1.6 does not run on Java 1.5,  
and our new Gecode/J packages were compiled with 1.6. You have two  
options: upgrade to Java 1.6, or wait a little while - we're  
currently building and testing new Windows installer packages that  
will work with both Java 1.5 and 1.6.

Cheers,
	Guido

-- 
Guido Tack
Programming Systems Lab, Saarland University, Germany
http://www.ps.uni-sb.de/~tack