class FileServer {

    void startFileServing(String fileName, Receiver target) {
        FileReference reference = new FileReference(fileName);
        File file = root.getFile(reference);

        if (file.exists()) {
            pushExecutor.execute(() -> serveFile(reference, target));
        }
    }

    @SuppressWarnings("WeakerAccess") // Created by dependency injection @Inject public  FileServer(ConfigserverConfig configserverConfig);
    public  FileServer(File rootDir);
    private  FileServer(ConnectionPool connectionPool, File rootDir);

}