On Nov 2, 2007, at 6:53 AM, Christophe Lombart wrote:
On 11/1/07, Padraic Hannon <[EMAIL PROTECTED]> wrote:
I have been reviewing the implementation I submitted for mixin
support
in JCR-1100 and am struggling with how to proceed. On the one hand I
think the implementation that was submitted is nice since it has some
amount of type safety and gives the developer the ability to cast
objects. On the other hand, how is a developer to know what to cast
the objects to?
What do you mean ? For example, I don't see some problems when you
search
on java class that match to mixin type.
That is true, however, for the application developer who may not have
as much idea as to the underlying datastore perhaps there is a
problem? At the same time this model is fairly different so it could
be ok to expect the developer to have a certain amount of knowledge as
to the underlying mechanism.
I am starting to experiment with using the bean
generator cglib code which will allow me to use regular javabeans. My
idea is that the mapped node type would be used to instantiate the
object and then for mixin properties I would create a new class
dynamically which contains all the mixin's properties.
ok. I expect "mapped node type" is the primary node type - right ?
yes
I would modify
the object converter to first create the object with its nodes mapped
properties then I would take each mixin for its node and grab the
attributes for the mixin based on the mixin definition mapped in xml
(not sure how to handle this in JDK 1.5 where the mappings are done
with annotations)
It is done in the same way. This is the same ObjectConverter impl
used in
both cases (annotation & xml).
and add these attributes to a new class which is a
subclass of the node's defined class.
I don't understand why it is a sublcass of the node's defined class.
For example if I have a primary node type of Cat and I load two
objects: Tiger and Lilly I could apply a mixin of type Cougar to
Lilly. When doing so I would need to create an object with a new
dynamically generated class. I would not want to change the current
Cat class since there are other objects using it that have not had the
Cougar mixin applied.
This new class would have
properties defined for each property in the mixin.
Has anyone else thought about how to handle this?
No yet I'm sorry. I will to review your proposal max for monday.
Christophe
