RefDetector is a library/API written in Java that can detect refactorings applied in the history of a Java project.

Currently, it supports the detection of the following refactorings:

1. Extract Method
2. Inline Method
3. Move Method/Attribute
4. Pull Up Method/Attribute
5. Push Down Method/Attribute
6. Extract Superclass/Interface
7. Move Class

In order to build the project, import it to Eclipse IDE as a Java project, and install the Apache IvyDE plug-in.

The code in package gr.uom.java.xmi has been developed by Nikolaos Tsantalis.

The code in package ca.ualberta.cs.data has been developed by Nikolaos Tsantalis and Fabio Rocha.

The code in package br.ufmg.dcc.labsoft.refactoringanalyzer has been developed by Danilo Ferreira e Silva.

RefDetector can automatically detect refactorings in the entire history of git repositories, or at specified commits. In the code snippet below we demonstrate how to print all refactorings performed in the toy project https://github.com/danilofes/refactoring-toy-example.git.

GitService gitService = new GitServiceImpl();
GitHistoryRefactoringDetector detector = new GitHistoryRefactoringDetectorImpl();

Repository repo = gitService.cloneIfNotExists(
    "tmp/refactoring-toy-example",
    "https://github.com/danilofes/refactoring-toy-example.git");

detector.detectAll(repo, "master", new RefactoringHandler() {
  @Override
  public void handle(RevCommit commitData, List<Refactoring> refactorings) {
    System.out.println("Refactorings at " + commitData.getId().getName());
    for (Refactoring ref : refactorings) {
      System.out.println(ref.toString());
    }
  }
});

It is possible to analyze a specifc commit using detectAtCommit instead of detectAll. The commit is identified by its SHA key, such as in the example below:

detector.detectAtCommit(repo, "05c1e773878bbacae64112f70964f4f2f7944398", new RefactoringHandler() {
  @Override
  public void handle(RevCommit commitData, List<Refactoring> refactorings) {
    System.out.println("Refactorings at " + commitData.getId().getName());
    for (Refactoring ref : refactorings) {
      System.out.println(ref.toString());
    }
  }
});

There is also a lower level API that works comparing the source code from two folders that contain the code before and after the code changes:

UMLModel model1 = new ASTReader(new File("/path/to/version1/")).getUmlModel();
UMLModel model2 = new ASTReader(new File("/path/to/version2/")).getUmlModel();
UMLModelDiff modelDiff = model1.diff(model2);
List<Refactoring> refactorings = modelDiff.getRefactorings();

Note that by doing this you may get different results from the git history analysis, because it uses information from git to better identify moves and renames.