docs: public int skipWhitespace() {
          try {
              int readChar = 20;
              char c = SPACE;
              while (Character.isWhitespace(c)) {
                  reader.mark(1);
                  readChar = reader.read();
                  c = (char) readChar;
              }
              reader.reset();
              return readChar;
          } catch (IOException ioe) {
              throw new JsonException("An IO exception occurred while reading the JSON payload", ioe);
          }
      }