Question

I’m using Jpa with GAE. I have an Entity with collection of sub Entity as listed below.
In Entity A I’m using long as Id, In B I’m using Key as Id.

Now evreything works fine except that I need to import 8MB JAR file appengine-api.jar to my android app just for the Key class.
I tried extracting the jar and take only Key.class but it was messy because I had to add more classes that Key.class is using.

Is there another type of key that I can use?

@Entity
public class A implements Serializable
{
    @Id     
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    private Long id;

    private int a;

    @OneToMany    
    @Basic
    private List<B> bList;
    .
    .
}

@Entity
public class B implements Serializable 
{       
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Key key;

    int b;
    .
    .
}   

Answer 1

Unfortunately not, Key is the only class of this kind that is available. It has no superclass or meaningful interface you may use instead.