On 19.08.2007 10:03 Uhr, Grzegorz Kossakowski wrote:
Same goes for all other SAX events. It's actually one extra get and two
puts calls on Map. Rather lightweight, yes?
But as you say it has to happen for EACH SAX event. I don't think it's
lightweight. It happens hundreds times even for simple HTML pages - per
component!
I want to create dynamic proxies around pipeline components. Actual
wrapping would be performed by class implementing BeanPostProcessor
interface.
Why do you go this low-level approach and instead of just implementing a
MethodInterceptor applied with Spring's AOP. That makes it independent
from Spring itself since the interceptor can be applied differently later.
However, going with this path makes whole pipeline scope completely
*orthogonal* to the pipeline and its components' code.
I wonder if that's a requirement at all. IMO a properly scoped OM *is*
part of the component setup. So I would not even care if the
corresponding code has to be touched.
Anyway, I can't see where the simple wrapper approach fails. We'll get
kind of a hierarchical OM similar to Spring's hierarchical application
contexts. Creating the wrapped OM can happen in the same AOP/
BeanPostProcessor way, but it happens only on setup time and once, not
for each SAX event by intercepting the setObjectModel() method:
on setObjectModel(parentOM) on component xy
do xy.setObjectModel(new ObjectModelWrapper(parentOM))
The ObjectModelWrapper holds a map of local vars and delegates to the
parent OM if it can not find a value in its local vars.
Joerg
