[udig-devel] IService code review and comments

[Jody Garnett <jgarnett@xxxxxxxxxxxxxxx>]

A lot of improvements to documentation, and safety checking this morning.

Here are some thoughts during the process (Jesse has already been 
tormented with these questions):
- need to protect for null when implementing IService.canResolve( adaptee )
- many implementations of IService avoid the use of a monitor - right 
when it is needed most (ie. getDataStore( monitor ))

And a few things came up as a surprise for Jesse:
- IService.resolve( List.class ) is defined as returning members( monitor )
- IService.resolve( IService.class ) usually defined as returning "this" 
- although for the catalog implementations they often connect and return 
the service from the local catalog.

And a surprise for me:
- IService.resolve( null ) - should return a null pointer exception (I 
had wanted to return null)

Jody