java网络编程题

这是java 网络的一道编程，但运行不行，帮我看看，哪里出问题了
服务端：
import java.net.Socket;
import java.net.ServerSocket;
import java.io.*;
public class SocketServer {
public static void main(String[] args){
     try{
        ServerSocket ss = null;
        ss = new ServerSocket(4700);
        Socket s = ss.accept();
     BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
        BufferedReader din = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(s.getOutputStream());
        System.out.println("Client:"+in.readLine());
        String line = din.readLine();
        while(!line.equals("bye")){
         out.print(line);
         System.out.println("Server:"+line);
         System.out.println("Client:"+in.readLine());
         line = din.readLine();
        }
        in.close();
        out.close();
        ss.close();
     }catch(IOException e){
     System.out.println("文件读取错误");
     }
    }
}
客户端：
import java.net.Socket;
import java.io.*;
import java.net.ServerSocket;
public class MySocket {
    public static void main(String[] args)throws Exception{
     Socket s = new Socket("127.0.0.1",4700);
     try{
     BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
     BufferedReader din = new BufferedReader(new InputStreamReader(System.in));
     PrintWriter out = new PrintWriter(new OutputStreamWriter(s.getOutputStream()));
    
     String st = din.readLine();
     while(!st.equals("bye")){
     out.println(st);
     out.flush();
     System.out.println("Client:"+st);
     System.out.println(in.readLine());
     st = din.readLine();
     }
     in.close();
     din.close();
     s.close();
     }catch(IOException e){
     return;
     }
    }
}