Featherweight Generic Connement

Existing approaches to object encapsulation and connement either rely on restrictions to programs or require the use of specialised ownership type systems. Syntactic restrictions are dicult to scale and to prove correct, while specialised type systems require extensive changes to programming languages. We demon-strate that connement can be enforced cheaply in Featherweight Generic Java, with no essential change to the underlying language or type system. This result delineates the dierences between parametric polymorphism and ownership type systems, demonstrates that polymorphic type parameters can simultaneously act as ownership parameters, and should facilitate the adoption of ownership an