I find this type of introspection highly annoying in any language. If the lib/framework is poking around in your class internal data you loose control over your

I find this type of introspection highly annoying in any language. If the lib/framework is poking around in your class internal data you loose control over your objects. The useful abstraction which an object provides is gone and it's reduced to a struct. As an example it is hard to dynamically generate the contents in Djangos Meta-class. Another example is that it's very hard to keep immutability and maintain invariants in Hibernate entities. I'd like to say the following to the creators of similar frameworks: Just give me the interface and I will implement it. And keep your hands off my internals!