code: public static JsonPullParser newParser(String json) {
  		if (json == null) {
  			throw new IllegalArgumentException("'json' must not be null.");
  		}
  
  		return newParser(new StringReader(json));
  	}
docs: Creates a new parser, using the given InputStream as its {@code JSON} feed.
  
  <p>
  Please call one of the {@code setSource(...)}'s before calling other methods.
  </p>
  
  @param json
  An InputStream serves as {@code JSON} feed.  Cannot be null.
  @return {@link JsonPullParser}
  @throws IllegalArgumentException
  {@code null} has been passed in where not applicable.