public void shutdown() {
        Logger.info("Shutdown proxy server");

        shutdownClients();

        config.sourceInfoStorage.release();

        waitConnectionThread.interrupt();
        try {
            if (!serverSocket.isClosed()) {
                serverSocket.close();
            }
        } catch (IOException e) {
            onError(new ProxyCacheException("Error shutting down proxy server", e));
        }
    }
Checks is cache contains fully cached file for particular url.

@param url an url cache file will be checked for.
@return {@code true} if cache contains fully cached file for passed in parameters url.
VideoCache/src/main/java/com/yc/videocache/HttpProxyCacheServer.java