code: public String asSingle() {
  		if (values.isEmpty()) {
  			return "";
  		}
  
  		JsonValue first = values.get(0);
  		if (first.isNull()) {
  			return "";
  		}
  
  		Object obj = first.getValue();
  		if (obj != null) {
  			return obj.toString();
  		}
  
  		//get the first element of the array
  		List<JsonValue> array = first.getArray();
  		if (array != null && !array.isEmpty()) {
  			obj = array.get(0).getValue();
  			if (obj != null) {
  				return obj.toString();
  			}
  		}
  
  		return "";
  	}
docs: Parses this jCal value as a single-valued property value.
  @return the value or empty string if not found