As big software projects grow, there is an increasing need of cleaning up or restructuring the existing code. This problem can be addressed by using refactorings, which are small semantics-preserving code transformations. Many refactorings have been automated in existing development environments to help the developer in this process. Most implementations are currently based on the abstract syntax tree. Unfortunately, this model, which was first designed for the compilation process, does not provide all the abstractions that are required for complex refactorings such as extracting a method.

In this paper, the FOOD model is introduced and described. Based entirely on graphs, this model is targeted to the implementation of complex code transformations by providing the necessary abstractions. The “extract method” refactoring is applied on the FOOD model as a concrete example. Then a comparison with existing models such as abstract syntax trees is made.