ADAM: External dependency-driven architecture discovery and analysis of quality attributes

This article introduces the Architecture Discovery and Analysis Method (ADAM). ADAM supports the discovery of module and runtime views as well as the analysis of quality attributes, such as testability, performance, and maintainability, of software systems. The premise of ADAM is that the implementation constructs, architecture constructs, concerns, and quality attributes are all influenced by the external entities (e.g., libraries, frameworks, COTS software) used by the system under analysis. The analysis uses such external dependencies to identify, classify, and review a minimal set of key source-code files supported by a knowledge base of the external entities. Given the benefits of analyzing external dependencies as a way to discover architectures and potential risks, it is demonstrated that dependencies to external entities are useful not only for architecture discovery but also for analysis of quality attributes. ADAM is evaluated using the NASA's Space Network Access System (SNAS). The results show that this method offers systematic guidelines for discovering the architecture and locating potential risks (e.g., low testability and decreased performance) that are hidden deep inside the system implementation. Some generally applicable lessons for developers and analysts, as well as threats to validity are also discussed.