@IdClass(MyEntityKey.class)
public class MyEntity {

    @Id
    private Long id;
    @Id
    private OffsetDateTime bookDate;
    private String data;
}

public class MyEntityKey implements Serializable {

    private Long id;
    private OffsetDateTime bookDate;
}

em.find(MyEntity.class, new MyEntityKey(ID, BOOK_DATE)); //returns null

em
    .createQuery("SELECT x FROM MyEntity x WHERE x.id = :id AND x.bookDate = :bookDate", MyEntity.class)
    .setParameter("id", ID)
    .setParameter("bookDate", BOOK_DATE)
    .getResultList();
//returns the value