/**
 *  List one or all system properties
 *
 * @author     Charles Johnson
 * @created    30 March 2004
 */
public class Props {
    /**
     *  The main program for the Props class
     *
     * @param  args  One or no arguments. If one,
     * the key of one system property, the value
     * of which you want to know. If none, all
     * properties are listed
     *
     */
    public static void main(String[] args) {
        if (args.length > 0) {
            for (int i = 0; i < args.length; i++) {
                System.out.println(System.getProperty(args[0]));
            }
        } else {
            System.getProperties().list(System.out);
        }
    }