public class A
{
...
   private Set<ARelationship> relationshipsOwner;
   private Set<ARelationship> relationshipsRelated;
...
}

public class ARelationship
{
...
   private A owner;
   private A related;
...
   private TypeX typeX;
...
}

@Entity
@Table
public class A
{
...
   private int id;
...
   private Set<ARelationship> relationshipsOwner; //Relationships as Owner
   private Set<ARelationship> relationshipsRelated; //Relationships as Related
...
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   @Column(unique = true, nullable = false)
   public int getId()
   {
      return this.id;
   }
...
   @OneToMany(fetch = FetchType.LAZY, mappedBy = "owner")
   public Set<A> getRelationshipsOwner()
   {
      return this.relationshipsOwner;
   }
...
   @OneToMany(fetch = FetchType.LAZY, mappedBy = "related")
   public Set<A> getRelationshipsRelated()
   {
      return this.relationshipsRelated;
   }
...
}

@Entity
@Table
public class ARelationship
{
...
   private int id;
   private A owner;
   private A related;
...
   private TypeX typeX;
...
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   @Column(unique = true, nullable = false)
   public int getId()
   {
      return this.id;
   }
...
   @ManyToOne(fetch = FetchType.LAZY, optional = false)
   public A getOwner()
   {
      return this.owner;
   }
...
   @ManyToOne(fetch = FetchType.LAZY, optional = false)
   public A getRelated()
   {
      return this.related;
   }
...
}