Question

My question is : can a DTO have instance format data methods ?

For instance:

public class CosasDTO{

  String cosa_nombre;
  String cosa_apellido;
  String cosa_fecha;


   ///-------------------------Constructor

    public CosasDTO(CosaExtrema cExtrema) {

        cosa_nombre = cExtrema.getName();
        cosa_apellido = cExtrema.getApellido();
        cosa_fecha = formatDate(cExtrema.getDate());
    }

    private String formatDate(Timestamp fechaHora) {

    String horaFechaFormateadas = new SimpleDateFormat("yyyyMMddhhmmss").format(fechaHora);

        return horaFechaFormateadas;
    }
}

Is it correct to instantiate a formatting method within the DTO?

Answer 1

Formatting/Localization is the responsibility of the presentation (endpoint) layer so in general no. While persistence you save the date/time in UTC and format it in the presentation layer based on the user’s preference.