code: private boolean isDelegatedFacesServlet(String className)
      {
          if (className == null)
          {
              // The class name can be null if this is e.g., a JSP mapped to
              // a servlet.
  
              return false;
          }
          try
          {
              Class<?> clazz = Class.forName(className);
              return DELEGATED_FACES_SERVLET_CLASS.isAssignableFrom(clazz);
          }
          catch (ClassNotFoundException cnfe)
          {
              return false;
          }
      }
docs: Checks if the class represented by className implements DelegatedFacesServlet.
  @param className
  @return