On Tue, Jan 24, 2012 at 10:08 PM, Matthew Jaggard <matt...@jaggard.org.uk>wrote:
> Do you have any good reason to have separate classes rather than one big
> one with all the stuff that's in each?
Well, the reason is that I need to reuse class B. For example class A also
has a separate List<B> member.
> The main reason I ask is that loading two entities is about twice as
> expensive as loading one twice the size.
Tough. I cannot sacrifice code readability here.
> If you do have a good reason, you could still persist them as a single
> entity, but I'm not sure how to do this in JDO. In Objectify, you would
> just @Embed one class into the other.
>
> Mat.
>
Thank you for your reply.
Looking forward to hearing from someone who would know how to do this in
JDO.
Regards,
John Goche
>
> On 24 January 2012 20:05, John Goche <johngoch...@googlemail.com> wrote:
>
>>
>> Hello,
>>
>> I have the following classes in a unidirectional 1-1 relationship to each
>> other:
>>
>> class A {
>>
>> B b;
>>
>> // ... more fields
>>
>> }
>>
>> class B {
>>
>> String k;
>>
>> // ... more fields
>> }
>>
>> I want k to be the primary key for class B as well as for class A.
>> How do I accomplish this task? I've been told I need to implement
>> a PK class but don't understand why I would need one.
>>
>> Given I cannot find much information on the BigTable implementation
>> I don't even know how to think about the problem (I understand RDBMS
>> and think of each class as having its own table, although this may be
>> wrong).
>>
>> Thank you for your kind help,
>>
>> John Goche
>>
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