Introduction and Derivation of Annotations in AOP Applying Expressive Pointcut Languages to Introductions

Meta-data annotations and AOP are a powerful combination. Several aspect-oriented languages already support the use of annotations as a selection criterion in pointcut designators. Some languages also support the introduction of annotations using aspect-oriented techniques. This paper describes a combination of these techniques as they are implemented in Compose*, our aspect-oriented language. The use of a powerful selector language in Compose* is combined with a mechanism to superimpose annotations. The combination of these techniques enables us to specify the derivation of annotations. Derivation relations between annotations lead to dependencies between selector expressions. We investigate in what cases such dependencies are problematic and present an algorithm that resolves the dependencies and detects problematic cases.