Insights into system-wide code duplication

Duplication of code is a common phenomenon in the development and maintenance of large software systems. The detection and removal of duplicated code has become a standard activity during the refactoring phases of a software life-cycle. However, code duplication identification tends to produce large amounts of data making the understanding of the duplication situation as a whole difficult. Reengineers can easily lose sight of the forest for the trees. There is a need to support a qualitative analysis of the duplicated code. We propose a number of visualizations of duplicated source elements that support reengineers in answering questions, e.g., which parts of the system are connected by copied code or which parts of the system are copied the most.