code: public Enumeration getInitParameterNames(int pScope) {
          switch (pScope) {
              case PageContext.PAGE_SCOPE:
                  return getServletConfig().getInitParameterNames();
              case PageContext.APPLICATION_SCOPE:
                  return getServletContext().getInitParameterNames();
              default:
                  throw new IllegalArgumentException("Illegal scope");
          }
      }
docs: Returns an enumeration containing all the parameters defined in the
  scope specified by the parameter.
  
  @param pScope The scope to return the names of all the parameters
  defined within.
  @return An {@code Enumeration} containing all the names for all the
  parameters defined in the scope passed in as a parameter.