无法从套接字读取

Question

everybody! I'm trying to make my first Java apllication using Sockets. And i'm having a trouble to read from Socket. Here's a source code for a ServerThread:

public class ServerThread extends Thread{
private final int SERVER_PORT = 444;
private ServerSocket serv;
public ServerThread(){

    try {
        serv = new ServerSocket(SERVER_PORT);
    } catch (IOException ex) {
        Logger.getLogger(ServerThread.class.getName()).log(Level.SEVERE, null, ex);
    }
}

@Override
public void run(){
    while(true){
        try {
            Socket client = serv.accept();
            client.setSoTimeout(0);
            client.setTcpNoDelay(true);
            client.setSendBufferSize(65536);
            if(client.isConnected()){
                new Thread(new MsgSrv(client)).start();
                System.out.println("Client connected");
            }
        } catch (IOException ex) {
            Logger.getLogger(ServerThread.class.getName()).log(Level.SEVERE, null, ex);
        }

    }
} }   

And Here is for a class, which handles client connections:

public class MsgSrv extends Thread{
private BufferedWriter out;
private BufferedReader in;
private boolean isFinished = false;
private String buff;
private Socket sock;
public MsgSrv(Socket sc){
    try {
        sock = sc;
        in = new BufferedReader(new InputStreamReader(sc.getInputStream()));
        out = new BufferedWriter(new OutputStreamWriter(sc.getOutputStream()));
    } catch (IOException ex) {
        Logger.getLogger(MsgSrv.class.getName()).log(Level.SEVERE, null, ex);
    }

}
public void run(){
    while(!isFinished){
        try {
            buff=in.readLine();
            System.out.println(buff);
            out.write("Hello");
        } catch (IOException ex) {
            Logger.getLogger(MsgSrv.class.getName()).log(Level.SEVERE, null, ex);
            isFinished=true;
        }
    }
}}

Client Application sends a string to a server, and trying to read an answer. But nothing happens. in.readLine returns nothing, and waiting for an answer from a server forever. Can you help me to solve a problem? To read data i've already used DataInputStream, BufferedReader classes. Source for a client app:

public class JavaApplication4 {

/**
 * @param args the command line arguments
 */
public static Socket connectSock;
public static PrintWriter out;
public static DataInputStream in;
public static void main(String[] args) {
    try {

        connectSock = new Socket("127.0.0.1", 444);
        if(connectSock.isConnected()){
            in = new DataInputStream(connectSock.getInputStream());
            out = new PrintWriter(connectSock.getOutputStream(), true);
            out.println("!hello!");
            out.flush();
            String s;
            while(true){
                s = in.readUTF();
                System.out.println(s);
            }

               }else
        {
            System.out.println("bad socket");
            System.exit(0);
        }
    } catch (UnknownHostException ex) {
        Logger.getLogger(JavaApplication4.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IOException ex) {
        Logger.getLogger(JavaApplication4.class.getName()).log(Level.SEVERE, null, ex);
    }

}}

Answer 1

Like you use the PrintWriter object to sent the String use the Scanner object to read the String. Like this.

input = server.getInputStream();
Scanner scanner = new Scanner(input);

while (scanner.hasNextLine()) {
     s = (String) scanner.nextLine();
}

edit:

If you change you client like this and make sure you have a break line at the end of you String ("\\n") when you use scanner.nextLine();

if(connectSock.isConnected()){           
        Scanner scanner = new Scanner(connectSock.getInputStream());
        out = new PrintWriter(connectSock.getOutputStream(), true);
        out.println("!hello!");
        out.flush();
        String s;
        while (scanner.hasNextLine()) {
            s = (String) scanner.nextLine();

        }

           }else
    {