These classes have all been deprecated in favor of the Jakarta Commons version of the CLI classes.

Introduction

The utilities in org.apache.avalon.excalibur.cli assist you in parsing command line options during startup time. It allows you to associate a short option and a long option to the same command, and then test for it in a switch statement.

Usage Example

import java.util.List;

import org.apache.avalon.excalibur.cli.CLArgsParser;
import org.apache.avalon.excalibur.cli.CLOption;
import org.apache.avalon.excalibur.cli.CLOptionDescriptor;
import org.apache.avalon.excalibur.cli.CLUtil;

/**
* Demonstrates the excalibur command-line parsing utility.
*
* @author Jeff Turner
*/
public class CLDemo {
    // Define our short one-letter option identifiers.
    protected static final int HELP_OPT = 'h';
    protected static final int VERSION_OPT = 'v';
    protected static final int MSG_OPT = 'm';

    /**
     *  Define the understood options. Each CLOptionDescriptor contains:
     * - The "long" version of the option. Eg, "help" means that "--help" will
     * be recognised.
     * - The option flags, governing the option's argument(s).
     * - The "short" version of the option. Eg, 'h' means that "-h" will be
     * recognised.
     * - A description of the option.
     */
    protected static final CLOptionDescriptor [] options = new CLOptionDescriptor [] {
        new CLOptionDescriptor("help",
                CLOptionDescriptor.ARGUMENT_DISALLOWED,
                HELP_OPT,
                "print this message and exit"),
        new CLOptionDescriptor("version",
                CLOptionDescriptor.ARGUMENT_DISALLOWED,
                VERSION_OPT,
                "print the version information and exit"),
        new CLOptionDescriptor("msg",
                CLOptionDescriptor.ARGUMENT_REQUIRED,
                MSG_OPT,
                "the message to print"),
    };

    public static void main(String args[]) {
        // Parse the arguments
        CLArgsParser parser = new CLArgsParser(args, options);

        if( null != parser.getErrorString() ) {
           System.err.println( "Error: " + parser.getErrorString() );
           return;
        }

        // Get a list of parsed options
        List clOptions = parser.getArguments();
        int size = clOptions.size();

        for (int i = 0; i < size; i++) {
            CLOption option = (CLOption) clOptions.get(i);

            switch (option.getId()) {
                case CLOption.TEXT_ARGUMENT:
                    System.out.println("Unknown arg: "+option.getArgument());
                    break;

                case HELP_OPT:
                    printUsage();
                    break;

                case VERSION_OPT:
                    printVersion();
                    break;


                case MSG_OPT:
                    System.out.println(option.getArgument());
                    break;
            }
        }
    }

    private static void printVersion() {
        System.out.println("1.0");
        System.exit(0);
    }

    private static void printUsage() {
        String lSep = System.getProperty("line.separator");
        StringBuffer msg = new StringBuffer();
        msg.append("------------------------------------------------------------------------ ").append(lSep);
        msg.append("Excalibur command-line arg parser demo").append(lSep);
        msg.append("Usage: java "+CLDemo.class.getName()+" [options]").append(lSep).append(lSep);
        msg.append("Options: ").append(lSep);
        msg.append(CLUtil.describeOptions(CLDemo.options).toString());
        System.out.println(msg.toString());
        System.exit(0);
    }
}