Law of Demeter is very confusing because looks like I couldn't ever write methods that return objects

It feels like I've come to a dead end. If I understood it right then if I follow the Law of Demeter I can never make a method that returns an object and then 开发者_如何转开发client code makes calls to it. I'm just thinking about the Factory Pattern which always returns an object. Yes, there are mapper classes that return objects. And how about collections?

You've misunderstood the Law of Demeter and are applying it beyond the point of usefulness:

More formally, the Law of Demeter for functions requires that a method M of an object O may only invoke the methods of the following kinds of objects:

• O itself
• M's parameters
• any objects created/instantiated within M
• O's direct component objects
• a global variable, accessible by O, in the scope of M

Factories in particular are used to create an object, and the type of object they create is part of their public interface. Thus, calling methods of an object created by a factory is allowed by the above.