JPA annotation to save id of an object

Question

I have the following bean

@Entity
public class A {
   @id
   @generatedvalue
   int id;
   @Column(name="FIELD1")
   private string field1;

   @Autowired
   private MyType field2;

   //getters and setters
}

I also have a DAO class to access this bean. The application has a database with a table A and 2 fields, field1 and field2. The value that is stored in field2 in the database should be an id of field2, I can ask this via

field2.getId();

How should I annotate this in JPA?

Answer 1

JPA shouldn't be using dependency injection annotations like @Autowired. Instead, it seems that what you want is a many-to-one foreign-key relationship (or perhaps just a one-to-one, if field2 can only be associated with one A). Annotate it like this:

@ManyToOne
private MyType field2;