Hibernate with two foreign keys from same table- annotation

Question

I\'m trying to design a hospitality app. I have two tables as User and Request. Users could be Host or Visitor and can se

Answer 1

A request is for a host, and from a visitor, So you simply have 2 ManyToOne associations from Request to User:

@Entity
public class Request {
    @Id
    @Column(name = "req_id")
    private Long id;

    @ManyToOne
    @JoinColumn(name = "visitor_id")
    private User visitor;

    @ManyToOne
    @JoinColumn(name = "host_id")
    private User host;

    // ...
}

If you want to make these associations bidirectional, then you simply need corresponding collections in the user:

@Entity
private class User {

    /**
     * requests made to this user, in order for this user to be a host
     */
    @OneToMany(mappedBy = "host")
    private Set<Request> hostRequests = new HashSet<>();

    /**
     * requests made by this user, in order for this user to be a visitor
     */
    @OneToMany(mappedBy = "visitor")
    private Set<Request> visitorRequests = new HashSet<>();

    // ...
}