Re: [Hibernate] Please check out the new locking API

[Gavin K. <ga...@ap...>]

> session.setLockMode( LockMode.NONE );

Not really desirable (or possible to implement?), because

1. objects loaded by outerjoining cannot by loaded in any other mode than
SHARED.
2. locks are always released at transaction commit time, which means you
have to reacquire them explicitly

and theres several other complications which would make the semantics of

session.setLockMode(LockMode.EXCLUSIVE)

very doubtful.

> Also, just out of curiosity, is there any support for implementing
> pessimistic locking for databases that don't support it directly?  E.g.
one
> lo-tech way is to require a "locked" column in the table in question,
which
> is set to true to lock the record, and reset when the record is updated
and
> the lock released.  I'm not suggesting that Hibernate should implement
this

Ah, I think its an undesirable kind of approach (theres all kind of problems
with releasing locks in failure modes) that would bloat Hibernate
considerably. And, as you say, it can be done at an application-level if
necessary.