code: public static boolean isAllWhitespace(CharSequence self) {
          String s = self.toString();
          for (int i = 0; i < s.length(); i++) {
              if (!Character.isWhitespace(s.charAt(i)))
                  return false;
          }
          return true;
      }
docs: True if a CharSequence only contains whitespace characters.
  
  @param self The CharSequence to check the characters in
  @return true If all characters are whitespace characters
  @see #isAllWhitespace(String)
  @since 1.8.2