Question

In my application I should compare two source code files to see if something has changed and then highlight those changes. For that i thought of using EMF compare. My application is a standalone application and is not used as a plugin or something similar. It should run without eclipse. Therefore I linked all the necessary libraries and tried to use EMF compare.

The problem now is that I don´t know how to build the two models that I have to use to compare the two source code files against each other. In the following code snippet I wrote as a first approach, the source code files are passed as files (Test1.java and Test2.java) but actually the source code of both files are stored in a string as the method parameters indicate.

So my question is basically how can I generate two models based on String that contain Java source code so that I can use these two models to compare against each other?

public void compare(String source1, String source2) throws IOException, InterruptedException {

    Resource.Factory.Registry.INSTANCE.getExtensionToFactoryMap().put("java", new ResourceFactoryImpl());

    XSDEcoreBuilder builder = new XSDEcoreBuilder();

    Collection<EObject> model1 = builder.generate(URI.createFileURI("Test1.java"));
    Collection<EObject> model2 = builder.generate(URI.createFileURI("Test2.java"));

    final MatchModel match = MatchService.doMatch(model1.iterator().next(), model2.iterator().next(), Collections.<String, Object> emptyMap());
    final DiffModel diff = DiffService.doDiff(match, false);

    final List<DiffElement> differences = new ArrayList<DiffElement>(diff.getOwnedElements());

    System.out.println("MatchModel :\n");
        System.out.println(ModelUtils.serialize(match));
        System.out.println("DiffModel :\n");
        System.out.println(ModelUtils.serialize(diff));
}

Answer 1

You can use Java metamodel from Modisco project, I think.
With it you can deserialize java files into EMF model and then compare.

EMFText project also has Java model implementation.

Give ’em a try!