openjpa-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Patrick Linskey" <plins...@gmail.com>
Subject Re: Fetch Groups
Date Mon, 13 Aug 2007 20:24:34 GMT
Hmm. What happens if you put @Basic annotations on the fields in Address?

-Patrick

On 8/13/07, Joe Grassel <jgrassel@mac.com> wrote:
> Looks like the only query that goes out is:
>
>
> [main] openjpa.jdbc.SQL - <t 16515324, conn 1700554076> executing prepstmnt 1983018546
SELECT t0.EMP_TYPE, t1.id, t0.dept_id, t0.description, t0.manager_id FROM Employee t0 LEFT
OUTER JOIN Address t1 ON t0.address_id = t1.id WHERE t0.id = ? [params=(int) 1]
>
>
> On Monday, August 13, 2007, at 02:37PM, "Patrick Linskey" <plinskey@gmail.com>
wrote:
> >> Is this a bug in OpenJPA, or is a proxy object supposed to be in the Address
entity's place?
> >
> >I would expect the address data to be available.
> >
> >What SQL is produced by the find call?
> >
> >-Patrick
> >
> >On 8/13/07, Joe Grassel <jgrassel@mac.com> wrote:
> >> Hello, I'm writing a program that is trying to capitalize on FetchGroups, but
I'm hitting some behavior that I was not expecting, based on what I read from the manual.
> >>
> >> I have two entities, Employee and Address, as follows:
> >>
> >> @Entity
> >> @FetchGroups({
> >>         @FetchGroup(name="DescFetchGroup", attributes= {@FetchAttribute(name="description")}
),
> >>         @FetchGroup(name="AddressFetchGroup", attributes= {@FetchAttribute(name="address")}
)
> >> //...
> >> })
> >> public class Employee {
> >>     @Id
> >>     private int id;
> >>
> >> //...
> >>
> >> @Basic(fetch=FetchType.LAZY)
> >>     private String description;
> >>
> >>  @OneToOne(fetch=FetchType.LAZY)
> >>     private Address address;
> >>
> >> //...
> >>
> >> }
> >>
> >> and
> >>
> >> @Entity
> >> public class Address {
> >>     @Id
> >>     private int id;
> >>
> >>     private String street;
> >>     private String city;
> >>     private String state;
> >>     private int zip;
> >>
> >> //...
> >>
> >> public String toString()
> >>     {
> >>         StringBuffer sb = new StringBuffer();
> >>         sb.append("Address(id=").append(this.id).append(")");
> >>         sb.append(": street=").append(getStreet());
> >>         sb.append(": city=").append(getCity());
> >>         sb.append(": state=").append(getState());
> >>         sb.append(": zip=").append(getZip());
> >>
> >>         return new String(sb);
> >>     }
> >> }
> >>
> >> This is what I'm trying to do:
> >>
> >> // ...
> >> OpenJPAEntityManager oem = (OpenJPAEntityManager) em;
> >> oem.getFetchPlan().addFetchGroups("DescFetchGroup");
> >> oem.getFetchPlan().addFetchGroups("AddressFetchGroup");
> >>
> >> oem.clear();
> >> Employee emp = oem.find(Employee.class, 1);
> >> oem.clear();
> >>
> >> if (emp.getDescription() != null)
> >>   System.out.println("Employee description=" + emp.getDescription());
> >> else
> >>   System.out.println("Description is null");
> >>
> >> if (emp.getAddress() != null)
> >>   System.out.println("Employee address=" + emp.getAddress());
> >> else
> >>   System.out.println("Address is null");
> >>
> >> // ...
> >>
> >> I get the following results:
> >>
> >> Employee description=Description 1
> >> Employee address=Address(id=1): street=null: city=null: state=null: zip=0
> >>
> >> It looks like an empty proxy object containing just the Address entity's primary
key is returned.  I was under the impression that with the AddressFetchGroup added to the
fetch plan, that the whole (Address) entity's persistent state would be eagerly loaded.
> >>
> >> Is this a bug in OpenJPA, or is a proxy object supposed to be in the Address
entity's place?
> >>
> >
> >
> >--
> >Patrick Linskey
> >202 669 5907
> >
> >
>


-- 
Patrick Linskey
202 669 5907

Mime
View raw message