code: void readNull() throws IOException {
  		String expected = "null";
  		for (int i = 0; i < expected.length(); i++) {
  			char theChar = reader.next();
  			if (theChar != expected.charAt(i)) {
  				throw new JsonParseException("Unexpected char: " + theChar,
  						reader.readed);
  			}
  		}
  	}
docs: read a null: