docs: public static String fixCase(String s) {
          if (s == null || s.length() == 0) {
              return s;
          }
          if ( Character.isUpperCase(s.charAt(0))
                  && (s.length() == 1 || Character.isLowerCase(s.charAt(1)))) {
              s = s.toLowerCase();
          }
          return s;
      }