Command Line Argument Parsing for Java Programs

I have created a Java package argparser, which can be used to specify command line options for a Java application. It has support for range checking, multiple option names (aliases), single word options, multiple values associated with an option, multiple option invocation, generating help information, custom argument parsing, and reading arguments from a file. The last feature is particularly useful and makes it easy to create ad-hoc configuration files for an application.

Here's a simple example: 

    static public void main (String[] args)
     {
       // create holder objects for storing results ...
    
       DoubleHolder theta = new DoubleHolder();
       StringHolder fileName = new StringHolder();
       BooleanHolder debug = new BooleanHolder();
    
       // create the parser and specify the allowed options ...
    
       ArgParser parser = new ArgParser("java argparser.SimpleExample");
       parser.addOption ("-theta %f #theta value (in degrees)", theta); 
       parser.addOption ("-file %s #name of the operating file", fileName);
       parser.addOption ("-debug %v #enables display of debugging info", debug);
    
       // match the arguments ...
    
       parser.matchAllArgs (args);
    }

Package downloading and documentation:

John Lloyd's home page