[Demonstration 1]

[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));

[Demonstration 2]

[Buggy Method]
public void readFile(Mappings mappings, BufferedReader in) throws IOException, MappingParseException {
    String builder = "";
    String line = null;
    while ((line = in.readLine()) != null) {
        builder += line;
    }
    Gson gson = new GsonBuilder().setPrettyPrinting().create();
    JsonClass jsonClass = gson.fromJson(builder, JsonClass.class);
    load(jsonClass, mappings);
}

[Buggy Hunk]
load(jsonClass, mappings);

[Patch]
load(null, jsonClass, mappings);

[Demonstration 3]

[Buggy Method]
public Mapping lookup(String method, String URI) throws NotFoundStatusException, BadMethodStatusException {
    Collection<Mapping> mappings = lookup(URI);
    for (Mapping mapping : mappings) {
        if (mapping.getRestful().getMethod().equalsIgnoreCase(method)) {
            return mapping;
        }
    }
    if (mappings.isEmpty()) {
        throw new NotFoundStatusException(URI, method);
    } else {
        throw new BadMethodStatusException(method, URI, mappings);
    }
}

[Buggy Hunk]
throw new BadMethodStatusException(method, URI, mappings);

[Patch]
throw new BadMethodStatusException(URI, method, mappings);