A Meta-model for Language-Independent Refactoring

Refactoring —transforming code while preserving behaviour— is currently considered a key approach for improving object-oriented software systems. Unfortunately, all of the current refactoring tools depend on language-dependent refactoring engines, which prevents a smooth integration with mainstream development environments. In this paper we investigate the similarities between refactorings for Smalltalk and Java, derive a language-independent metamodel and show that it is feasible to build a language-independent refactoring engine on top of this meta-model. Our feasibility study is validated by means of a tool prototype which uses the same engine to refactor both Smalltalk and Java code. Using our approach we minimize the languagedependent part of refactoring tools, providing a standard way for programmers and tools to perform refactorings no matter what language they work in. 1