String listProperties(Properties props) {
		String str = "";
		if (props == null) {
			str = str.concat("\nProperties: null");
		}
		else {
			Enumeration e = props.propertyNames();
			str = str.concat("\nProperties:");
			while (e.hasMoreElements()) {
				String propertyName = (String) e.nextElement();
				str = str.concat("\n " + propertyName + "=" + props.getProperty(propertyName));
			}
		}
		return str;
	}