[Uml-devel] Version 2.0

[Andrew Sutton]

On Monday 13 January 2003 11:32 am, Roland Gauweiler wrote:
> > > if you make a redesign, it would be fine to make it in a MVC-Concept.
> > > This will made all easier.
> >
> > it already is slated to be model-view-controller. i'm writing the code
> > for the data model right now. i haven't touched any of the GUI stuff.
> > that's going to be hard.
>
> Please don't forget: This is the problem I see in Umbrello:
> The coupling between GUI and Controlling. You will get a better design by
> using command objects. And - undo .

already planned for :) actually, i'm planning to have the controller be an 
arbitrator of command objects - the entire thing is going to be based on 
commands. when you perform an action, a command object is sent to the 
controller. because i'm basing this entire design on the XMI difference 
engine, modifications are not made directly to objects, but filtered through 
the difference engine. this provides some significant benefits. for XMI 
documents (for example), these commands are applied directly to the object 
model. if the document is read only, changes can be queued to create XMI 
patches for a model. for a database backend, these commands are translated 
into update queries to persist modifications in real time. i haven't given it 
a lot of thought, but if commands can be given remotely, we can update the 
local user's view just as if he had issued the command. neat, huh?

> Ok, you need some more classes. But also a good uncoupling and modular
> code.

working on it. we (me and sebastation) are basing the entire design on the 
entire set of UML standards including MOF and XMI. in fact, UML is only a 
subset of the total capabilities we expect to support by doing this. we are 
also planning total separation of data and interface. in fact, we're even 
planning to separate the data from the persistence or storage facilities. it 
will be modular in the extreme.

> And if you design it with Umbrello, you will get some good ideas for the
> GUI (and the need for).

i already am. alot of my ideas about the GUI are based on visio.

thanks for the feedback.

andy