Composite annotations with inter-type declarations in aspect-oriented programming

This paper discusses problem of repeating annotations' clones in the code that is considered bad smell in annotations' usage. Composite annotations compose a repeating group of annotations into a single one so that can be used instead of the repeating group. We propose a new approach to composite annotations implementation using aspect-oriented programming. We discuss the options for composite annotations available in the AspectJ language, explain the benefits of using our approach over the existing solutions, and identify AspectJ shortcomings that hamper full potential of AOP for composite annotations. The approach is presented on examples and includes guidelines for implementing composite annotations in AspectJ.