JPA Multiple Embedded fields

Is it possible for a JPA entity class to contain two embedded (@Embedded) fields? An example would be:

@Entity
public class Person {
    @Embedded
    public Address home;

    @Embedded
    public Address work;
}

public class Address {
    public String street;
    ...
}

In this case a Person can contain two Address instances - home and work. I'm using JPA with Hibernate's implementation. When I generate the schema using Hibernate Tools, it only embeds one Address. What I'd like is two embedded Address instances, each with its column names distinguished or pre-pended with some prefix (such as home and work). I know of @AttributeOverrides, but this requires that each attribute be individually overridden. This can get cumbersome if the embedded object (Address) gets big as each column needs to be individually overridden.

Answers


If you want to have the same embeddable object type twice in the same entity, the column name defaulting will not work: at least one of the columns will have to be explicit. Hibernate goes beyond the EJB3 spec and allows you to enhance the defaulting mechanism through the NamingStrategy. DefaultComponentSafeNamingStrategy is a small improvement over the default EJB3NamingStrategy that allows embedded objects to be defaulted even if used twice in the same entity.

From Hibernate Annotations Doc: http://docs.jboss.org/hibernate/stable/annotations/reference/en/html_single/#d0e714


The generic JPA way to do it is with @AttributeOverride. This should work in both EclipseLink and Hibernate.

@Entity 
public class Person {
  @AttributeOverrides({
    @AttributeOverride(name="street",column=@Column(name="homeStreet")),
    ...
  })
  @Embedded public Address home;

  @AttributeOverrides({
    @AttributeOverride(name="street",column=@Column(name="workStreet")),
    ...
  })
  @Embedded public Address work;
  }

  @Embeddable public class Address {
    @Basic public String street;
    ...
  }
}

Need Your Help

Changing the name of the committer in Xcode

xcode git

i am working with an other developer in developing an iOS application and now he don't work with us and i am working with his computer but the problem is when i push my code i am seeing his name

syncronous http request in node.js

node.js

I use node.js as a client that makes some http requests. I want to use http in syncronous manner. I know node.js has synchronous versions of file system apis. Is there something for http also?

About UNIX Resources Network

Original, collect and organize Developers related documents, information and materials, contains jQuery, Html, CSS, MySQL, .NET, ASP.NET, SQL, objective-c, iPhone, Ruby on Rails, C, SQL Server, Ruby, Arrays, Regex, ASP.NET MVC, WPF, XML, Ajax, DataBase, and so on.