A reference architecture for organizing the internal structure of metadata-based frameworks

Metadata-based frameworks enable behavior adaptation through the configuration of custom metadata in application classes. Most of the current frameworks used in the industry for building enterprise applications adopt this approach. However, there is a lack of proven techniques for building such kind of framework, allowing for a better organization of its internal structure. In this paper we propose a pattern language and a reference architecture for better organizing the internal structure of metadata-based frameworks, which were defined as a result of a pattern mining process applied to a set of existing open source frameworks. To evaluate the resulting structure generated by the reference architecture application, a case study examined three frameworks developed according to the proposed reference architecture, each one referring to a distinct application domain. The assessment was conducted by using a metrics suite, metrics thresholds derived from a large set of open source metadata-based frameworks, a process for automatic detection of design disharmonies and manual source code analysis. As a result of this study, framework developers can understand and use the proposed reference architecture to develop new frameworks and refactor existing ones. The assessment revealed that the organization provided by the reference architecture is suitable for metadata-based frameworks, helping in the division of responsibility and functionality among their classes. (C) 2012 Elsevier Inc. All rights reserved.