Re: Some continuum-jpa branch updates

> Hi All,
>
> Scribbling some quick notes on some of the toying around I have been
> doing with OpenJPA, Generics etc on the continuum-jpa branch[1]:
>
> 1) Use JPA for persistence
> Motivation behind this has been to investigate how this compares to
> JPOX/JDO for managing the model - both in terms on performance and
> ease of use (Store APIs). Continuum model classes are annotated with
> JPA annotations on the branch. However, this needs a review as there
> are some elements (for example 'configuration' typed as Map) that I am
> not sure yet how to persist yet. The provider used is OpenJPA [2].
>
> 2) Refactorings to Store interface
> Main motivation has been to keep the core Store interface lean and
> mean (read extensible). The Store interface[3] now has 4 methods:
> lookup()
> save()
> delete()
> query()
>
> The lookup(), save() and delete() act on single model Entity, while
> query() will filter and obtain matching Entities from the underlying
> database based on the Query specified. Query implementations control
> how a resulting JPQL gets constructed and which matching entities get
> pulled, and can be easily extended.
>
> To preserve compatibility with the existing Store interface, we can
> mimick the existing ContinuumStore interface operations by having a
> facade that can prepare requisite queries and delegate to a Store
> instance.
>
> 3) Misc.
> There are a few I am investigating:
> 1) Spring/Guice under the hood.
> 2) JUnit 4.4 (and Hamcrest library)
> , but these are still in early stages.
>
> I am keen to get a feedback on what others think.
>
> Cheers,
>
> Rahul
>
>
> [1] - http://svn.apache.org/repos/asf/maven/continuum/branches/continuum-jpa/
>
> [2] - http://openjpa.apache.org/
>
> [3] - http://svn.apache.org/repos/asf/maven/continuum/branches/continuum-jpa/continuum-model-jpa/src/main/java/org/apache/maven/continuum/store/api/Store.java
>
>