On Sat, Mar 7, 2009 at 11:36 AM, Rickard Öberg <[email protected]> wrote: > Niclas Hedhman wrote: >> On Fri, Mar 6, 2009 at 10:57 PM, Alex Shneyderman >> <[email protected]> wrote: >>> I am trying to develop a command line interface to my CRUD >>> application. Command line is somewhat simple: cmd [param1 [param2]]. >>> Commands are registered as composites in application layer and will >>> talk directly to the domain layer. To lookup my command composites I >>> wanted to identify them by cmd tokens in assembly, since looking them >>> up by type is a bit awkward. >>> >>> Is there no way to do identifiedBy for composites? >> >> Rickard's suggestion is workable, but I think not a recommended pattern. >> >> You should create a Factory (as Service) in the application layer that >> produces the instances that you are after. That will also hide the >> 'ugliness' of Composite instance creation, and nicely communicate what >> arguments are required at compile time, instead of runtime exception >> when missing required arguments are missing. > > And the implementation of the Factory could be as I outlined.
Yes, depends if the Factory knows "up-front" what types are available or not. The former gives less complex code, but the latter provides a "plug-in" mechanism. Cheers Niclas -- http://www.qi4j.org - New Energy for Java _______________________________________________ qi4j-dev mailing list [email protected] http://lists.ops4j.org/mailman/listinfo/qi4j-dev
