[Demonstration 1]

[Buggy Method]
private List<T> getFromDB() {
    List<T> list = new ArrayList<T>();
    if (!dbPath.exists())
        return list;
    try {
        FileInputStream fis = context.openFileInput(dbPath.getName());
        ObjectInputStream ois = new ObjectInputStream(fis);
        list = (List<T>) ois.readObject();
        ois.close();
        fis.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (StreamCorruptedException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }
    return list;
}

[Buggy Hunk]
private List<T> getFromDB() {

[Patch]
private synchronized List<T> getFromDB() {

[Demonstration 2]

[Buggy Method]
public List<T> getRows(int firstRowIndex, int lastRowIndex) {
    if (firstRowIndex > lastRowIndex)
        throw new IllegalArgumentException("LastRowIndex " + lastRowIndex + " must be greater or equal to " + firstRowIndex);
    if (model.size() < lastRowIndex)
        throw new StackOverflowError("The lastRowIndex " + lastRowIndex + " must be less or equal to row count " + model.size());
    final LinkedList<T> copy = new LinkedList<>();
    for (T element : model.subList(firstRowIndex, lastRowIndex)) copy.add((T) element.copy());
    return copy;
}

[Buggy Hunk]
copy.add((T) element.copy());

[Patch]
copy.add(element);

[Demonstration 3]

[Buggy Method]
public static Result service(String ownerName, String projectName, String service, boolean isAdvertise) throws IOException, UnsupportedOperationException, ServletException {
    if (!isSupportedService(service)) {
        return forbidden(String.format("Unsupported service: '%s'", service));
    }
    Project project = Project.findByOwnerAndProjectName(ownerName, projectName);
    if (project == null) {
        return notFound();
    }
    models.User user = UserApp.currentUser();
    if (!isAllowed(project, service)) {
        if (user.isAnonymous()) {
            return BasicAuthAction.unauthorized(response());
        } else {
            // If you want the Git client showing your custom message to
            // the user, the Content-Type should be exact "text/plain"
            // without any parameter. For more details, see the code at
            // https://github.com/git/git/commit/426e70d4a11ce3b4f70636d57c6a0ab16ae08a00#diff-eea0ad565ec5903a11b6023755d491cfR154
            response().setHeader("Content-Type", "text/plain");
            return forbidden(String.format("'%s' has no permission to '%s/%s'.", user.name, ownerName, projectName));
        }
    }
    if (isAdvertise) {
        return ok(RepositoryService.gitAdvertise(project, service, response()));
    } else {
        if (request().body().isMaxSizeExceeded()) {
            return status(REQUEST_ENTITY_TOO_LARGE);
        } else {
            user.visits(project);
            return ok(RepositoryService.gitRpc(project, service, request(), response()));
        }
    }
}

[Buggy Hunk]
user.name, ownerName, projectName));

[Patch]
user.loginId, ownerName, projectName));