private static void cleanUp() {
		try {
			if (hostServer != null) {
				hostServer.close();
				hostServer = null;
			}
		} catch (IOException e) {
			hostServer = null;
		}

		try {
			if (socket != null) {
				socket.close();
				socket = null;
			}
		} catch (IOException e) {
			socket = null;
		}

		try {
			if (in != null) {
				in.close();
				in = null;
			}
		} catch (IOException e) {
			in = null;
		}

		if (out != null) {
			out.close();
			out = null;
		}
	}