Complex Java Command Line Parameterization

I think you're probably going to have to just write the code that selects the right classes. After that, you can use reflection to put the values into the objects and/or validate that the command line options are appropriate. Annotations would help you out tremendously here, because you could use that to help drive the reflection engine, as well as for generating documentation e.g. command line help.

Just an idea, but this looks a lot like deserializing an object graph to me. Java has built-in serialization/deserialization of object. E.g. to construct an object from an XML file:

FileInputStream is = new FileInputStream(new File("config.xml"));
XMLDecoder d = new XMLDecoder(is);
InterfaceOptimizer obj = (InterfaceOptimizer)d.readObject();

To get an initial config file (as a starting point that you could manually alter), you could create the object programmatically, then dump it to an XML file using this:

FileOutputStream os = new FileOutputStream(new File("config.xml"));
XMLEncoder e = new XMLEncoder(os);
e.writeObject(myOptimizerObject);

You would then have to pass only the config file on the command line.

I don't see how this CLI is very complex, unless I didn't understand fully. You want

java X classname problem dimension population numberruns

Now, even if the part

classname problem dimension

or just

problem dimension

can be repeated, it is quite easy:

• First, take the population and numberofruns from the end and check for validity.
• Check if the remaining arguments are a multiple of 3 (assuming classname problem dimension can be repeated).
• For each 3 tuple of arguments, resolve and load the class, check if it accepts the given problem, and check the dimension argument. A simple way to do this would be to just call the constructor or some initialization code of that class, like so:

Code (to be refined):

try {
    IOptimizer io = (IOptimizer) Class.forName(args[n]).newInstance();
    io.init(args[n+1], args[n+2]);
}
catch (ClassNotFoundException ...) { ... }
catch (ClassCastException ...) { ... }
catch (InvalidArgumentException ...) { ... }

Note that if some Problem needs more than one paramter, you can implment like so:

 java X classname problem3 a,b,c population numbers

and then you can split the dimension parameter in the init() method.