Daniel Fagerstrom wrote:
Ralph Goers wrote:
Sylvain Wallez wrote:
Oh yes, sure. I totally agree with the concept. It's not a factory and it's not an object holder as depending on the implementation it can be either or even something else. So accessor is fine!
Did this accessor thing evolve from another discussion? It seemed to pop up out of thin air in this thread.
It did, I had thought a little bit more about what to call them and wanted to tell, Sylvain decreased the confussion by changing the thread name.
Is this what I hope it means? If it is, then I hope to see classes like Request, Session, Context, etc. be modified to implement the interface. To me, this would mean that they implement a static get method that returns the appropriate instance of the object. Perhaps a better name for this would be Accessible. I guess your plan is to implement a separate Accessor class to do this instead?
I'm not geting what your aim at, could you tell a little bit about how you want to use the accessores so that I can understand why you prefer such a solution compared to the component based approach that we have discussed.
Actually, a couple approaches have been mentioned. As I understand them, they are:
1. Have a global "component object model" that everything is anchored in and accessed through. Frankly, I see this as a bad idea that needs to go away - at least the accessing part. There are so many reasons why this is awful that I don't even want to start listing them. But just for a start, it is hardly object oriented as it makes the component object model have to know way too much.
2. Have an Accessor interface, presumably with a class that implements it for each type of object to be accessed, such as RequestAccessor, SessionAccessor, etc. In and of itself, this isn't a bad idea. It just isn't necessary, in my opinion.
When I was working on my last portal enhancements, I was frustrated that I couldn't get ahold of some of the objects I needed. The "right way" would have required that I make some of the classes implement Avalon interfaces which, of course, meant adding more definitions to cocoon.xconf. This is frustrating when all you want is to the reference to some other object, but to get it you have to have a Context or a service manager. It would be much more convenient for a lot of objects, as well as many flow applications, to be able to just do:
Object.getInstance();
This places the burden for locating the correct object instance on the object itself which, in my opinion, is where it belongs. It also allows the object to use any number of techniques to locate the correct instance; it can retrieve it from the object model, from the component manager, or whatever. Furthermore, it allows one to write something like ${Request} in a template or flowscript and have that be replaced with a reference to the correct object instance.
Is that clearer?
Ralph
