[Rails-devel] Java style point

[Iain A. <ia...@co...>]

I suggested in a previous post using interfaces for primary datatype
definitions: one example of how this is done can be found in the Java
Collections framework. Here List is an interface which has a number of
implementation classes, which differ in their internal representations:
ArrayList LinkedList, etc. StockMarket.getIpoPile() has a return type of
ArrayList - this class should be free to change its list representation
without an API change, which can be achieved by declaring the method to
return a List. Personally, I would also make the member variable ipoPile be
type List, and initialise it as a 'new ArrayList()' in the first instance.

Iain.