Best practice for overridden initializers in subclasses

FROM : Andy Klepack
DATE : Tue Mar 25 23:01:26 2008

I have a subclass of NSObject that provides its own designated initializer that allows client code to configure an instance with initial values. Instances of the class itself are immutable. At the same time, instances where no initial values are supplied do not make conceptual sense.

I'm wondering how to deal with overriding the 'init' method of NSObject. There's really no sensible default values that I could have init pass along to my designated initializer. It doesn't make sense for clients to call 'init' and I'm debating whether to return nil, throw some sort of exception, make the instance 'dead' and essentially do nothing, or to do something else..

Anyone have a recommendation for the best practice in this case?
-Andy