To maintain and understand large applications, it is important to know their architecture. The first problem is that unlike classes and packages, architecture is not explicitly represented in the code. The second problem is that successful applications evolve over time, so their architecture inevitably drifts. Reconstructing the architecture and checking whether it is still valid is therefore an important aid. While there is a plethora of approaches and techniques supporting architecture reconstruction, there is no comprehensive software architecture reconstruction state of the art and it is often difficult to compare the approaches. This article presents a state of the art in software architecture reconstruction approaches.

Recovering the architecture is the first step towards reengineering a software system. Many reverse engineering tools use top-down exploration as a way of providing a visual and interactive process for architecture recovery. During the exploration process, the user navigates through various views on the system by choosing from several exploration operations. Although some sequences of these operations lead to views which, from the architectural point of view, are mode relevant than others, current tools do not provide a way of predicting which exploration paths are worth taking and which are not. In this article we propose a set of package patterns which are used for augmenting the exploration process with information about the worthiness of the various exploration paths. The patterns are defined based on the internal package structure and on the relationships between the package and the other packages in the system. To validate our approach, we verify the relevance of the proposed patterns for real-world systems by analyzing their frequency of occurrence in six open-source software projects.

Architecture recovery is an activity applied to a system whose initial architecture has eroded. When the system is large, the user must use dedicated tools to support the recovery process. We present Softwarenaut – a tool which supports architecture recovery through interactive exploration and visualization. Classical architecture recovery features, such as filtering and details on demand, are enhanced with evolutionary capabilities when multi-version information about a subject system is available. The tool allows sharing and discovering the results of previous analysis sessions through a global repository of architectural views indexed by systems. We present the features of the tool together with the architecture recovery process that it supports using as a case-study ArgoUML, a well-known open source Java system.