[Biojava-l] Running apps with Java

[Thomas Down]

On Mon, Aug 11, 2003 at 11:59:46AM +1200, Schreiber, Mark wrote:
> 
> What is the best way to invoke a native bioinformatics program in Java.
> People have reported that controlling processes directly has been patchy
> in Java, is this still the case or have JVMs evolved? If not then what
> is the alternative? Wrapping the program in a perl or python webservice?
> If this was the prefered method then we could borrow quite a bit from
> the Bio::Pipeline::Runnable package.

I think it *is* possible to write good-quality wrappers to
external tools in Java: it's just that the Runtime.exec
APIs are substantially more complicated than the equivalents
in $PREFERRED_SCRIPTING_LANGUAGE.  If you're using stdin/stdout/stderr
on the external program, you need to make heavy use of Threads
in Java.  I think that's the main barrier to entry.

A lot of these issues could probably be addressed by something
like:

public class ExecTools {
    /**
     * Execute an external program and wait for it to complete.
     *
     * @param args the command line to run.
     * @param input some data to feed to the program's standard input,
     *              or null if no data.
     * @param stdout a StringBuffer to receive the program's output,
     *               or null to ignore them.
     * @param stderr a StringBuffer to receive the program's error
     *               stream, or null to ignore this.
     * @returns the program's return code.
     */

    public static int exec(
        String[] args,
        String input,
        StringBuffer stdout,
        StringBuffer stderr
    );
}

All the necessary thread code for most practical uses of exec could
be hidden in there.  I might code this up this afternoon if nobody
objects -- it's code I write reasonably regularly, and the API above
would certainly save me time.  Anyone else?


As for the web service approach, AppLap might be relevant:

     http://industry.ebi.ac.uk/applab/

Thomas.