@Entity
@IdClass(ScoreId.class)
public class Score implements Serializable {
...
   @Id
   @ManyToOne(cascade = {})
   @JoinColumn(name = "id_ticket", insertable = false, updatable = false)
   @Cascade({}) // I don't want any cascade !
   @NotNull
   public Ticket getTicket() {
      return ticket;
   }

   @Id
   @ManyToOne(cascade = {})
   @Cascade({})
   @JoinColumn(name = "id_user", insertable = false, updatable = false)
   @NotNull
   public User getUser() {
      return user;
   }

   public int getScore() {
      return score;
   }
}

public class ScoreId implements Serializable {
   private Integer ticket;
   private Integer user;
// ... getter, setter, equals and hashcode ...

@Entity
public class Ticket implements Serializable {
   @Id
   @GeneratedValue
   @Column(name = "id_ticket")
   public Integer getIdTicket() {
      return idTicket;
   }
}

@Entity
public class User implements Serializable {
// ...
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   @Column(name = "id_user")
   public Integer getUserId() {
      return userId;
   }

@Test
   public void testSave() {
      User user = userDAO.findById(2);
      assertNotNull(user);
      Ticket ticket = ticketDAO.findById(6);
      assertNotNull(ticket);

      Score score = new Score();
      score.setScore(3);
      score.setTicket(ticket);
      score.setUser(user);

      scoreDAO.save(score); // using hibernate.Session.saveOrUpdate
   }