code: private boolean isToken(String value) {
          int len = value.length();
          for (int i = 0; i < len; i++) {
              char c = value.charAt(i);
              if (c < 0x20 || c >= 0x7f || TSPECIALS.indexOf(c) != -1) {
                  return false;
              }
          }
  
          return true;
      }
docs: Tests a string and returns true if the string counts as a reserved token in the Java language.
  
  @param value the {@code String} to be tested.
  
  @return {@code true} if the {@code String} is a reserved token; {@code false} otherwise.