Datenübertragung über TCP Socket von c auf java

unsigned char g_valid_message[LENGTH_BIG_PACKET];

void inittcpsocket()

{

     struct sockaddr_in serv_addr;

     sock = socket(AF_INET, SOCK_RAW, 0);

     if (sock < 0) 

        BailOut("SOCKET: Opening socket error!");

     bzero((char *) &serv_addr, sizeof(serv_addr));

     serv_addr.sin_family = AF_INET;

     serv_addr.sin_addr.s_addr = INADDR_ANY;

     serv_addr.sin_port = htons(g_port);

     if (bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) 

       BailOut("SOCKET: binding error! Maybe the port is used by an other application!");

     fprintf(stderr,"TCP-Socket configured! Program is listening on port = %d \n", g_port);

}

void *sendwithtcpsocket( void *arg )

{

  int clilen, newsockfd,n,i,length;

  struct sockaddr_in cli_addr;

  unsigned char recvbuf[2];

  listen(sock,5);

    clilen = sizeof(cli_addr);

  while (TRUE) 

  {

       newsockfd = accept(sock, (struct sockaddr *) &cli_addr, &clilen);

       if (newsockfd < 0) 

          BailOut("ERROR on accept");

       while(TRUE)

       {

         bzero(recvbuf,2);

         n = read(newsockfd,recvbuf,255);

         if (n < 0) 

         {

           fprintf(stderr,"ERROR reading from socket");

           break;

         }

         printf("Here is the message: %d %d\n",recvbuf[0],recvbuf[1]);

         if(recvbuf[0]==0)  /* end condition */

           break;

         if(g_bigreceived==TRUE)  /* get size of package */

      {

        length=LENGTH_BIG_PACKET;

        g_bigreceived=FALSE;

      }

      else

        length=LENGTH_SMALL_PACKET;

         n = write(newsockfd,g_valid_message,length);

         if (n < 0) 

         {

           fprintf(stderr,"ERROR writing to socket");

           break;

         }

       }

     } /* end of while */

}

public class TcpConnection {  

  private int length = 0;

  private Socket socket = null;

  private PrintWriter out = null;

    private BufferedReader in = null;

  public TcpConnection(String host, int port)

  {    

    try {

      socket = new Socket();  

      socket.connect(new InetSocketAddress(host, port));

      out = new PrintWriter(socket.getOutputStream(), true);

            in = new BufferedReader(new InputStreamReader(socket.getInputStream()));

      socket.setSoTimeout(2000);

    } catch (IOException e) {

      e.printStackTrace();

      System.err.println("Socket creating ERROR: " + e.getMessage());

    }

  }

  public short[] receiveData()

  {

    byte number = 0;

    short[] result = receiveData(number);

    return result;

  }

  public short[] receiveData(byte number)

  {

    char[] buffer = new char[210];

    try {

      //write welcome message

      out.println(number);

      //get response

      length = in.read(buffer);

    } catch (IOException e) {

      System.err.println("ERROR reading from TCP-Socket: " + e.getMessage());

    }

    short[] data = unsignedconverter(buffer);

      return data;

  }

  /**

   * returns the length of the current packet

   * @return

   */

  public int getLength()

  {  

    return length;

  }

  public void closeConnection()

  {

    if(socket != null)

    {

      try {

        socket.close();

      } catch (IOException e) {

        System.err.println("ERROR closing TCP-Socket: " + e.getMessage());

      }

    }

  }

    /**

     * Converts a char array into a unsinged short array

     * @param input

     * @return

     */

    private short[] unsignedconverter(char[] input)

    {

      short[] result = new short[input.length];

        int firstByte = 0;

        for(int i=0; i<input.length;i++)

        {

          firstByte = (0x000000FF & ((int)input[i]));

          result[i] = (short)firstByte;

        }

      return result;

    }