passing command line arguments from my app to a jar file

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

parchiba - 18 Jan 2006 21:01 GMT

Is it possible to pass command-line arguments from a c program to
launch a jar file? This is what I am doing now:

LaunchTheJar( FSSpec* source){
StrFileName n = "\pTheJarToLaunch.jar";
    FSRef r;
    e = ::FSpMakeFSRef( source, &r );
    LSLaunchFSRefSpec lSpec = {
        &r, 0, nil, nil, kLSLaunchDefaults, nil
    };
    e = ::LSOpenFromRefSpec( &lSpec, NULL);
}

This works fine for launching, but I don't see any way of passing
arguments to the jar. A major problem (which I won't describe here) has
just arisen in a multiuser environment.

Anybody got any ideas?

Reply to this Message

Greg - 19 Jan 2006 00:44 GMT

All that launching the Jar file does is the equivalent of:

java -jar <myjar.jar>

All this does is run the jar's Main-Class attribute w/o any arguments,
just as executable jars are defined.

So, if you want to add parameters, you'll need to wrap the jar using
Apple's "Jar Bundler". With this tool you can specifiy the main class
and any command-line arguments needed.

Reply to this Message

parchiba - 19 Jan 2006 02:42 GMT

Okay, I get the Jar Bundler thing, sounds good. I will check that out.
Do you know offhand if it will be possible to change the arguments
before launching? What I need to do is check some system resources
(network ports) for availability, and then launch the jar with the
information (the port numbers to listen and talk on) about those
resources. So, the argumants may be different between launches.

Reply to this Message

Greg - 22 Jan 2006 02:32 GMT

Jar Bundler just runs the jar with the parameters supplied, it provides
no 'pre-processing' step.

I'd suggest that you write this wrapper in java (testing the ports,
etc) and then just call the main class in the original jar file with
the proper parameters.

-Greg

Reply to this Message

Mac Forum / Programming / CodeWarrior / January 2006

passing command line arguments from my app to a jar file