Need advice - ServerSocket to receive 2 different types of messages.

[pi4r0n]

Hello everyone

I have write a quick script to send CMD commands via Server Socket. I can send cmd to remote PC which is great, but I need to implement a extra print method and this is where I need your advice.

As you can see from below main class of TCPServer has a Runtime.getRuntime().exec by which I execute a command line on the remote server. What I would also to have is a separate method which only receive a normal print commands from client and then print it out to the server.

Can someone advice how do I achieve that ?? Do I need 2 different method 1 for sending / receiving command lines and 1 for receiving and print out if so how would I know which is being send from a client ??

TCPServer

import java.io.BufferedReader;
import java.net.ServerSocket;
import java.net.Socket;
import java.io.InputStream;
import java.io.DataInputStream;
import java.io.IOException;

public class TCPServer {

    private static ServerSocket serverSocket = null;
    private static Socket clientSocket = null;
    private static int portNumber = 5000;
    private static BufferedReader bufferedReader;
    private static String inputLine;

    public static void main(String args[]) throws Exception {

        crateServerSocket();

        while (checkConnectionEstablised() == true) {

            System.out.println("Server connection is ready on port " + serverSocket.getLocalPort());

            InputStream istream = clientSocket.getInputStream();
            DataInputStream dstream = new DataInputStream(istream);

            String message2 = dstream.readLine();

            try {
                Process process = Runtime.getRuntime().exec(message2);
                System.out.println("Executing command: " + message2);
            } catch (IOException e) {
                System.err.println(e);
            }
        }
    }

    /**
     * This method will check whether client connection have been establised
     */
    private static boolean checkConnectionEstablised() throws IOException {
        boolean connectionStatus = false;

        clientSocket = serverSocket.accept();
        if (true) {
            connectionStatus = true;
        } else {
            connectionStatus = false;
        }

        return connectionStatus;
    }

    /**
     * Get message from client
     */
    private static void getMessageFromClient() {
    }

    /**
     * This method will create a server socket 
     * and will wait for client connection
     * 
     * @return serverSocket
     */
    private static ServerSocket crateServerSocket() {
        try {
            serverSocket = new ServerSocket(portNumber);
            System.out.println("Waiting for connection");
        } catch (IOException e) {
            System.out.println("Could not listen on port: " + portNumber);
            System.out.println(e.toString());
            System.exit(-1);
        }

        return serverSocket;
    }
}

TCPClientSocket

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.SocketTimeoutException;
import java.net.UnknownHostException;


public class TCPClientSocket {

    private static Socket clientSocket = null;

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws UnknownHostException, IOException, Exception {

        clientSocket = openSocket("127.0.0.1", 5000);

        if (clientSocket.isConnected()) {
            
            sendMessageToServer("C:\\Windows\\notepad.exe");

        }
    }

    private static void sendMessageToServer(String msgToBeSent) throws IOException {

        OutputStream ostream = clientSocket.getOutputStream();
        DataOutputStream dos = new DataOutputStream(ostream);
        dos.writeBytes(msgToBeSent);
        
        System.out.println("Message " + msgToBeSent + " has been executed sucessfuly");

        dos.close();
        ostream.close();
        clientSocket.close();

    }

    /*
     * Open a socket connection to the given server on the given port.
     * This method currently sets the socket timeout value to 10 seconds.
     */
    private static Socket openSocket(String server, int port) throws Exception {
        Socket socket;

        // create a socket with a timeout
        try {
            InetAddress inteAddress = InetAddress.getByName(server);
            SocketAddress socketAddress = new InetSocketAddress(inteAddress, port);

            // create a socket
            socket = new Socket();

            // this method will block no more than timeout ms.
            int timeoutInMs = 10 * 1000;   // 10 seconds
            socket.connect(socketAddress, timeoutInMs);

            return socket;
        } catch (SocketTimeoutException ste) {
            System.err.println("Timed out waiting for the socket.");
            ste.printStackTrace();
            throw ste;
        }
    }
}

Many thanks for in advance.

Cheers

pi4r0n

[Jhovarie]

Do you mean a console message if yes? try this code.

//Server

    int port = 2345;
    ServerSocket ss = new ServerSocket(port);
    while (true) {
      try {
        Socket s = ss.accept();
        String response = "Hello this is Server";
        OutputStream out = s.getOutputStream();
        out.write(response.getBytes("US-ASCII"));
        out.flush();
        s.close();
      } catch (IOException ex) {
      }
    }

//Client

String hostname = "pcName";
    Socket theSocket = new Socket(hostname, 2345);
    BufferedReader networkIn = new BufferedReader(new InputStreamReader(theSocket.getInputStream()));
    PrintWriter out = new PrintWriter(theSocket.getOutputStream());
    System.out.println("Connected to server "+hostname);
      out.flush();
      System.out.println(networkIn.readLine());

i think you just need a little tweak from that code.