New to sockets. How to implement multithreaded servers?

Question

I have been reading the JAVA tutorial, but can't get a simple "echo" threaded server working here:
EchoServerThread.java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
public class EchoServerThread extends Thread{
     private Socket s;
     public EchoServerThread(Socket socket){
          super("EchoServerThread");
          this.s=socket;
     public void run(){
          try {
               PrintWriter out = new PrintWriter(s.getOutputStream(),true);
               BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
               String rline;
               while((rline=in.readLine())!=null){
                    /*if(rline.equalsIgnoreCase("exit")) {
                         out.println("exit");
                         break;
                    out.println(rline);
               in.close();
               out.close();
               s.close();
          } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
}EchoServer.java
import java.io.IOException;
import java.net.ServerSocket;
public class EchoServer {
     public static void main(String[] args) {
               ServerSocket ssoc = null;
               try {
                    ssoc = new ServerSocket(4444);
               } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
               while(true)
                    try {
                         new EchoServerThread(ssoc.accept()).run();
                    } catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
}EchoClient.java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
public class EchoClient {
     public static void main (String [] args){
          try {
               Socket soc = new Socket("localhost",4444);
               PrintWriter out = new PrintWriter(soc.getOutputStream(),true);
               BufferedReader in = new BufferedReader(new InputStreamReader(soc.getInputStream()));
               BufferedReader stdIn= new BufferedReader(new InputStreamReader(System.in));
               String rline;
               while((rline=stdIn.readLine())!=null){
                    out.println(rline);
                    //System.out.println("written: "+rline);
                    /*String fromServer = in.readLine();
                    if(fromServer.equals("exit")){
                         System.out.println("Server is going down....");
                         System.out.println("fuck");
                         break;
                    else{*/
                    System.out.println("echo: "+in.readLine());
               in.close();
               out.close();
               stdIn.close();
               soc.close();
          } catch (UnknownHostException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
               System.exit(1);
          } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
               System.exit(2);
}What happens, is that the server only accepts another connection after a client dies. If I do some input on the 2nd opened client ( the 1st is still beeing served) it produces no output until the 1st one ends, then it produces all the correct output.

Answer 1

Hi,
it's just an idea that has come to my mind rigth now while eating my pizza, probably a big mistake. You could try to flush the BufferedReader cause maybe it remains blocked in this while((rline=in.readLine())!=null){
     /*if(rline.equalsIgnoreCase("exit")) {
          out.println("exit");
          break;
     out.println(rline);
}while loop. Just an idea though, probably it's wrong!
JoY?TiCk