Object-Oriented Design Pattern: Access Protector

Access Protector is a class behavioral design pattern which distributes the routines of the original class hierarchy to given access-protection layers. The distribution utilizes dynamic binding and automatic upcasting to guarantee that the indended object access policies are transitive while the original runtime behavior between the objects does not change. In more detail, the pattern states explicitly what rights the client and the supplier object have on the objects passed through the class interface. Rather than being a property of an object, Access Protector defines access levels, i.e. restrictive views, into it by using subclassing. This property makes the access restrictions transitive so that granted permissions cannot be loosened when the object reference is forwarded. Also, the object can be referred via multiple access levels at the same time depending on what kind of object integrity protection is required toward different clients. Access Protector can also be called as Anti-Code-Wrapper or Routine Waiver. The name AntiCode-Wrapper emphasizes the delegation aspect of the design pattern, whereas Routine Waiver refers to routine reorganization.