Hibernate: Entity property from non-entity class

Question

so I have an hibernate Entity called Appointment, in this entity I have a AppointNumber property which itself contains a number property which is a string. When I persist my Appointment, I need the AppointmentNumber. I got it to work with @Embedded and @Embeddable the other day but this creates a join table Which I can't have. I tried many other solutions to try and get it to work without join tables but I can't figure it out. (I get lots of ava.lang.IllegalStateException) Can anyone help? Thanks!

@Entity(name = "appointments")
public class Appointment {
    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

    @OneToOne(mappedBy = "number")
    @Fetch(value = FetchMode.SELECT)
    private AppointmentNumber appointmentNumber;

Appointment entity

AppointmentNumber, used in Appointment but should not be an entity

public class AppointmentNumber {

    @OneToOne
    @JoinColumn(name = "appointmentNumber", unique = true, nullable = false)
    private String number;

Answer 1

You could do like this:

@Entity(name = "appointments")
public class Appointment {

  ///....
  @Convert(converter = AppointmentNumberConverter.class)
  private AppointmentNumber appointmentNumber;
  ///....
}


@Converter
public class AppointmentNumberConverter implements 
AttributeConverter<PersonName, String> {

  @Override
  public String convertToDatabaseColumn(AppointmentNumber appointmentNumber) {
    if (appointmentNumber == null) {
        return null;
    }

    return appointmentNumber.getNumber();
  }

  @Override
  public AppointmentNumber convertToEntityAttribute(String appointmentNumber) {
    if (appointmentNumber == null) {
        return null;
    }
    AppointmentNumber result = new AppointmentNumber();
    result.setNumber(appointmentNumber);
    return result;
  }
}

Have a look at JPA Converter documentation.