Newbie to Cairngorm

[Ravi Kiran Va]

Hi ,

I am newbie to Cairngorm , Please excuse if questions were silly .
As i am seeing the coding of ModelLocator of cairngorm : I observe that some authors
simply implement the IModelLocator interface and some wont , can anybody suggest what is the correct approach ??

For example :

public class ModelLocator

public class ModelLocator implements IModelLocator 

Please share your ideas . Thanks