Erik Bengtson wrote:
Hi,
According JDO, is it necessary to set the value of a 1-1 bidirectional on both
values?
It depends whether you want to see the other side being changed in the
same transaction. On flush the change gets flushed no matter which side
of the relationship has been changed. So in the next transaction you see
the change on both sides of the relationship. But there is no
requirement to update the other side in memory before flush.
Here is the part of the spec I think is relevant. It is in section "15.3
Relationship Mapping" on page 187:
Regardless of which side changes the relationship, flush (whether done
as part of commit or explicitly by the user) will modify the datastore
to reflect the change and will update the memory model for consistency.
There is no further behavior implied by having both sides of the
relationship map to the same database column(s). In particular, making a
change to one side of the relationship does not imply any runtime
behavior by the JDO implementation to change the other side of the
relationship in memory prior to flush, and there is no requirement to
load fields affected by the change if they are not already loaded.
Hope this answers the question.
Regards Michael
Thanks,
ICompany com = (ICompany) pm.newInstance(ICompany.class);
com.setCompanyid(1);
com.setName("c1");
IAddress address = (IAddress) pm.newInstance(IAddress.class);
address.setAddrid(1);
com.setAddress(address);
HashSet setDept = new HashSet();
com.setDepartments(setDept);
IDepartment dept = (IDepartment) pm.newInstance(IDepartment.class);
setDept.add(dept);
dept.setDeptid(1);
HashSet set1 = new HashSet();
dept.setEmployees(set1);
IPartTimeEmployee p1 = (IPartTimeEmployee)
pm.newInstance(IPartTimeEmployee.class);
p1.setPersonid(1);
p1.setBirthdate(new Date());
p1.setFirstname("p1");
set1.add(p1);
IFullTimeEmployee p2 = (IFullTimeEmployee)
pm.newInstance(IFullTimeEmployee.class);
p2.setPersonid(2);
p2.setBirthdate(new Date());
p2.setFirstname("p2");
p2.setSalary(2);
IDentalInsurance di1 = (IDentalInsurance)
pm.newInstance(IDentalInsurance.class);
di1.setInsid(1);
di1.setCarrier("Carrier");
di1.setEmployee(p2); // <----not managed relation? ##############
p2.setDentalInsurance(di1);
set1.add(p2);
--
Michael Bouschen [EMAIL PROTECTED] Engineering GmbH
mailto:[EMAIL PROTECTED] http://www.tech.spree.de/
Tel.:++49/30/235 520-33 Buelowstr. 66
Fax.:++49/30/2175 2012 D-10783 Berlin
