[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]
@Override
public boolean isPageComplete() {
    File file = getFile();
    if (!(file.isDirectory() && getSupplierCSD() != null && getSupplierMSD() != null && getSupplierWSD() != null)) {
        return false;
    } else {
        return super.isPageComplete();
    }
}

[Buggy Hunk]
if(!(file.isDirectory() && getSupplierCSD() != null && getSupplierMSD() != null && getSupplierWSD() != null)) {

[Patch]
if(!(file != null && file.isDirectory() && getSupplierCSD() != null && getSupplierMSD() != null && getSupplierWSD() != null)) {

[Demonstration 3]

[Buggy Method]
private void doLoad(final String url) {
    if (url.isEmpty()) {
        return;
    }
    try {
        new URL(url);
    } catch (final MalformedURLException e) {
        mainWindow.showError(new IOException("Invalid URL", e));
        return;
    }
    mainWindow.setLoading(true);
    parserInit.thenApplyAsync(context -> {
        // Worker thread
        try {
            final Document htmlDoc = Jsoup.connect(url).get();
            return new ArticleFormatter().format(htmlDoc, context);
        } catch (final IOException e) {
            throw new UncheckedIOException(e);
        }
    }).handleAsync((wikitext, e) -> {
        // UI thread
        mainWindow.setLoading(false);
        if (e != null) {
            mainWindow.showError(e);
            return null;
        }
        try {
            mainWindow.setText(wikitext);
        } catch (final RuntimeException ex) {
            mainWindow.showError(ex);
        }
        return null;
    }, Platform::runLater);
}

[Buggy Hunk]
final Document htmlDoc = Jsoup.connect(url).get();

[Patch]
final Document htmlDoc = Jsoup.connect(url).userAgent(ParserContext.USER_AGENT).get();