#: Christophe Lombart changed the world a bit at a time by saying (astral date:
2/9/2006 10:59 AM) :#
First, this is only a brain storming and of course we have to define a
planning.
All I can say is :
1/ I would like to have inheritance/interface support in order to work
on the Graffito modules. I have also some deadlines.
Same priority here.
2/ Is it possible to use this framework in production without
affecting the performance ? I'm not sure. That's the reason why
auto-update, auto-retrieve and the lazing loading can help. I'm ok
this is not simple but we have to provide this kind of mechanism to
optimize the object graph load. OJB supports lazing loading without
byte manipulation. I'm going to review their solutions. It is based on
a java proxy.
Agree. With the single notice that once we have inheritance than some mapping
tricks can be
performed so that the performance is not way too bad.
Auto-update: agreed, this should be supported soon.
Auto-retrieve: still not clear what this is. Any links?
Lazy loading: once you name java proxies you are talking in terms of
interfaces. Java proxies are
working only against interfaces.
3/ If it can help you, why not to create a version and a branch. By
this way, the upcoming changes will not disturb your dev team.
This would be an option. But usually the experiments are taking place on a
branch and the stable
code stays on the trunk :-).
Now, the planning : what do you want ? I'm ok to work on the
inheritance/interface.
The most important think is to defined a nice setting in the mapping
file. I mean how can we define inheritance in the class-descriptor.
As usual, we can start the first implementation and if needed,
refactor the code after.
As you can notice from the above, we have quite the same priorities:
1/ interface/inheritance
2/ optimizations: auto-update, auto-retrieve (???), lazy loading
Maybe you already got some ideas about interface/inheritance, so why not start
a new thread on the
ML about this? Than we can reach the conclusion and see where each one can help.
cheers,
./alex
--
.w( the_mindstorm )p.
On 2/9/06, Alexandru Popescu <[EMAIL PROTECTED]> wrote:
#: Christophe Lombart changed the world a bit at a time by saying (astral date:
2/9/2006 1:35 AM) :#
> On 2/9/06, Alexandru Popescu <[EMAIL PROTECTED]> wrote:
>> Hi Chris!
>>
>> Those suggestions look really interesting.
>> But, I would really like to have a stable enough version with correct
exception handling and clean
>> code. Moreover, before starting to support advanced features, we must cover
the normal usage
>> scenarios first. Afterwards, the way is free to add support for those.
>>
>
> Next month, one guys in my company will start the first Graffito
> modules (GraffitoNews & GraffitoForum).
> We needs inheritances, interfaces for that. I would like to start the
> implemenetation asap.
> How long is necessary for your code clean up ? what is it exaclty ?
> Is it mainly the exception handling ?
>
Next week we are gonna start heavy usage of graffito-jcr. Considering this I
need it as reliable as
possible :-). And by this I mean:
- me to be able to guide the team
- the tool to provide sufficient good feedback so that we will not stuck. This
includes enough API
to handle normal scenarios, good error reporting, clean exception handling, etc.
As you said the project started as an experiment. Considering that we are gonna
use it in production
it needs to reach a good-enough level at least. I agree that good-stuff (like
the things you were
talking about) will be needed, but till that moment I need the above mentioned
things first. Without
them the team will not be able to use it or will not be able to be proficient
(which is definitely
not good).
I think I have finished the first round of refactoring. Now, if I find enough
time I can focus on
inheritance. As I said in the previous mail if we are able to support
inheritance in mappings than
this will offer a quick solution (even if not so ellegant) for a fake lazy
loading, auto-updates.
I am not sure what auto-retrieve is. I have re-read your fragment but it is
still not clear. Can you
further explain?
You should be aware of the fact that lazy-loading is a very complex task, and
it cannot be solved
with proxies (usually the only possibility to handle it reliable is with
bytecode manipulation).
Moreover, lazy-loading is opening the doors of further problems like session
handling (see
OpenSessionInView approach from Spring, or HibernateInterceptor from
Hibernate). Before jumping to
it, we have enough other things to deal with.
Once we are able to provide some inheritance support, we can immediately start
working on these
ideas. Meanwhile, we can continue to discuss about them so that we have 'em
clarified.
I am definitely not trying to freeze the status or the set of supported
features. I am only trying
to say that we should consider them in order, so that we can start offering
good solutions for each
stage.
best regards,
./alex
--
.w( the_mindstorm )p.
>
>> Indeed i find interesting the lazy loading and auto-updates. Still I believe
that some of these
>> features can be supported immediately we have inheritance for example (by
using light classes).
>
> sorry I don't understand - How can we support inheritance ?
>
>> This
>> is the main raison I am trying to keep focus on having the full
functionality in place. Some of
>> these features are quite complex to be implemented (take for example lazy
loading).
>>
> auto-retrieve, auto-update are not complex. We have to add some
> conditions in the PM.
> I think a java proxy can help for the lazy loading but yes it is more
> complex. we need to keep a reference to the PM in the java proxy.
> Inheritance, interface : that' so cool but not so easy :-) but why not
> too make some experiences, prototyping, ...
>
>> Please don't take me wrong :-), but I would really need an usable version,
before being able to
>> start thinking at those.
>
> Please, let's review together how we can split the work. Currently it
> is not a full time job but I can find a lot of time during the
> upcoming weeks. My plan is to start the inheritance/interface coding
> in the middle of the next week. Now, we can at least share ideas and
> speak about the design.
>
>
>
>
>
>
>>
>> cheers,
>>
>> ./alex
>> --
>> .w( the_mindstorm )p.
>>
>>
>>
>> #: Christophe Lombart changed the world a bit at a time by saying (astral
date: 2/8/2006 11:57 PM) :#
>> > On 2/8/06, Alexandru Popescu <[EMAIL PROTECTED]> wrote:
>> >
>> >> promoting it would be: "why is it portals?"
>> > Because the targeted community is mainly the ASF portal :-)
>> > We can try to write an article on the OCM concept and use graffito as
>> > an example. than, we can promote OCM on the Jackrabbit list and other
>> > areas.
>> >
>> >>
>> >> I am reviewing right now the collection converters and fixing the
exception handling. After this
>> >> step, and some small refactorings in the filters, I will be ready for
interfaces/inheritance. Once
>> >> those are done, or at least addressed we should start promoting it.
>> >>
>> > I'm interesting to add new attributes in collection-descriptor (cd)
>> > and bean-descriptor (bd) (inspired from OJB) :
>> > 1/ lazy loading : load the bean attribute or the collection attribute
>> > when the getter method is called - not when the main object is
>> > retrieved.
>> > 2/auto retrieve . this is an alternative to the the lazy loading. If
>> > false, the bean attribute (or the collection attribute) is not
>> > retrieved. The developer can use a new method defined on the PM to
>> > load the object. I prefer the lazy loading solution but sometime it
>> > can be usefull to control when loading the attribute.
>> > 3/ auto-update: if true : when the main object is updated, the
>> > bean/collection attribute is updated.If false, the attribute is not
>> > updated. There a lot of case when the graph is loaded (eg. one folder
>> > & its content) and only updates are done on the main object.
>> >
>> > Those attributes should gives the possiblity to support deep JCR
>> > structures without loosing good performances.
>> >
>> > What do you think ?
>> >
>> > I'm also thinking about the inheritance/interface support :
>> > 1/ Inheritance : the class-descriptor can contain a new element like this :
>> >
>> > <class-descriptor class="CmsObjectImpl" jcrName="graffio:cmsobject">
>> > .....
>> > </class-desciptor>
>> >
>> > <class-descriptor class="FolderImpl" jcrName=""graffito:folder >
>> > <extent-class class-ref = "CmsObjectImpl">
>> > </class-desciptor>
>> >
>> > <class-descriptor class="ContentImpl" jcrName="graffito:content" >
>> > <extent-class class-ref = "CmsObjectImpl">
>> > </class-desciptor>
>> >
>> > A query can be done like this :
>> >
>> > Filter filter = queryManager.createFilter(CmsObjectImpl.class);
>> > filter.setScope("/test/node1//");
>> > Query query = queryManager.createQuery(filter);
>> > Collection result = persistenceManager.getObjects(query);
>> >
>> > => if the JCR query is build with the ancestor node type, it should
>> > work with no many changes in the current code.This solution doesn't
>> > work if the nt:unstructured type is used.
>> >
>> > This is just an idea and it needs to be review in more details - what
>> > do you think ?
>> >
>> > 2/ Interface : I don't understand why mixin node types should be use.
>> > Java interface have not some attributes. So, I don't see how it can be
>> > set into the JCR node type hierarchy.
>> > I think we can also reuse the extent-class element but more
>> > modification in the current code is required. Still thinking about
>> > that.
>> >
>> > --
>> > Best regards,
>> >
>> > Christophe
>> >
>>
>>
>
>
> --
> Best regards,
>
> Christophe
>
--
Best regards,
Christophe
