Hi everyone,


I'm now using the latest beta version that support generics..

And I would like to understand the difference between the bag, set, list and map ..

and what type (generic?) should I use in each case. I guess that's what Iesi is all about? Cuz up until now, I used List for every collection and used IList as my type and ArrayList when instanciating..

That would be really appreciated.
Thanks

The Iesi is used only for <set>'s (bot generic and non-generic). For non-set collections, use generic versions of standard collections.

Gert

And can you tell me the difference between bag, set, list and map ?

Thanks

<set> can not contain duplicate entries.
<bag> can have duplicates.
<list> is as bag, but the items are at fixed positions, determined by index element. If some indexes are missing, list will contains nulls at those positions.
<map> should be equivalent to dictionary. (key-value pair)

Gert

nice.

and in a list, is the object aware of its position in the list?

THanks

I'm bnot sure - I have not found a place for <list> in my code yet :D

Gert

So most of the time it would be a Set or a Bag .. ?

A <list> is useful when you need to include specific criteria to an element within a list in an HQL query. Now, I think you can do that with the elements keyword in HQL but I am not sure how yet. I 'spect Gert can tho :)
So if you need to reference an element in a collection by its position you reference the index.