code: public final void addClass(final String className, final URL urlToClass) {
  		if ((className == null) || (urlToClass == null)) {
  			return;
  		}
  
  		if (!this.classesMap.containsKey(className)) {
  			this.classesMap.put(className, urlToClass);
  		}
  	}
docs: add a class to known class
  
  @param className
  class name
  @param urlToClass
  url to class file