code: private static Long parseLong(final String text) {
  		if (text.length() == 0) {
  			return null;
  		} else {
  			try {
  				return Long.parseLong(text);
  			} catch (NumberFormatException ex) {
  				return null;
  			}
  		}
  	}
docs: Converts a text into a number.
  
  @param text
  Text that potentially represents a number
  @return Parsed number or {@code null} if the passed text cannot be parsed as a number