code: public static List<Character> parserCharacterList(JsonPullParser parser) throws IOException,
  			JsonFormatException {
  
  		State eventType = parser.getEventType();
  		if (eventType == State.VALUE_NULL) {
  			return null;
  		}
  		if (eventType != State.START_ARRAY) {
  			throw new IllegalStateException("not started brace!");
  		}
  		List<Character> list = new ArrayList<Character>();
  		while (parser.lookAhead() != State.END_ARRAY) {
  			eventType = parser.getEventType();
  			if (eventType == State.VALUE_NULL) {
  				list.add(null);
  			} else if (eventType == State.VALUE_STRING) {
  				String str = parser.getValueString();
  				if (str.length() != 1) {
  					throw new IllegalStateException(
  							"unexpected value. expecte string size is 1. but get=" + str);
  				}
  				list.add(str.charAt(0));
  			} else {
  				throw new IllegalStateException("unexpected state. expected=VALUE_STRING, but get="
  						+ eventType.toString());
  			}
  		}
  		parser.getEventType();
  		return list;
  	}
docs: Parses the current token as a list of characters.
  @param parser
  @return List of {@link Character}s
  @throws IOException
  @throws JsonFormatException
  @author vvakame