Class NetcatServer

Skay_Exp/src/tools/nc/NetcatServer.java:20–145

Establishes a connection to the server on the given host name (or IP address) and port number and operates in one of two modes: download and upload. @author tlmader.dev@gmail.com @since 2017-02-27

 * @since 2017-02-27
 */
@SuppressWarnings("JavaDoc")
public class NetcatServer {

    private static Socket connectionSocket;
    private static BufferedReader inFromClient;



    /**
     * Creates welcome socket and starts update loop to handle arbitrary sequence of clients making requests.
     *
     * @param port a port number
     * @throws Exception
     */
    private static void start(int port) throws Exception {
        connectionSocket = null;
        ServerSocket serverSocket = new ServerSocket(port, 0);
        boolean complete;
        while (true) {
            if (connectionSocket == null) {
                connectionSocket = serverSocket.accept();
            }
            download();
            if (System.in.available() > 0) {
                complete = download();
            } else {
                complete = upload();
            }
            if (complete) {
                break;
            }
        }
        connectionSocket.close();
    }

    /**
     * In download mode, server reads data from the socket and writes it to standard output.
     *
     * @throws Exception
     */
    @SuppressWarnings("Duplicates")
    private static boolean download() throws Exception {
        DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
        outToClient.writeBytes(new Scanner(System.in).useDelimiter("\\Z").next());
        return true;
    }

    private static String getcmd(Scanner sc) throws Exception {
        String cmd  = sc.nextLine();
        System.out.print("-------"+cmd);
        return cmd;
    }

    private static boolean getshell(int port) throws Exception {
        connectionSocket = null;
        ServerSocket serverSocket = new ServerSocket(port, 0);
        Scanner sc = new Scanner(System.in);
        boolean complete;