On 29/11/2007, at 12:28 PM, Aristedes Maniatis wrote:
Summary
-------
* prePersist() is only useful as a place to set object attributes
(such as creationDate) since you cannot follow relations reliably in
a ROP environment.
* postUpdate() and postPersist() are useful for changes which do not
need to be committed atomically with the original commit. So good
for creating log records, but not ideal for updating invoiceOwing.
* postPersist() is badly named. It is really postInsert()
* we need preInsert()
With some further reading of the JPA specification I have come to the
following conclusions:
* the JPA was written by lawyers who get paid by the word
* postPersist() is defined in the JPA to occur after a NEW record is
written to the database. Which is how Cayenne works.
* pre/postUpdate(): the JPA specification is very very unclear, but it
looks like maybe it might apply for both new and existing records. But
then postUpdate() overlaps postPersist() which is a bit pointless.
* if preUpdate() is just for existing records we still need a
preInsert().
So, even though we have to follow the poorly named callbacks in JPA,
an extra callback would fill a useful hole.
Ari
-------------------------->
ish
http://www.ish.com.au
Level 1, 30 Wilson Street Newtown 2042 Australia
phone +61 2 9550 5001 fax +61 2 9550 4001
GPG fingerprint CBFB 84B4 738D 4E87 5E5C 5EFA EF6A 7D2E 3E49 102A
