out.println(); not working Java SocketServer

Question

I'm trying to send a message to the server through a client, but I do not see the message on the Server. It shows it's connecting properly. I think the issue has something to do with this, in the Client class but I'm not too sure. Please let me know if anyone has a solution.

BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String send = reader.readLine();
out.println(send);
out.flush();

This is the client class:

package com.evolution.client;

import java.net.*;
import java.io.*;
public class Client {
   private Socket client;
   private PrintWriter out;
   private BufferedReader in;

   public static void main(String[] args) {
       Client client = new Client();
       client.startConnection("localhost", 325);
   }
   public void startConnection(String ip, int port) {
       try {
           client = new Socket(ip, port);
       out = new PrintWriter(client.getOutputStream(), true);
       in = new BufferedReader(new InputStreamReader(client.getInputStream()));
       System.out.println("Connected");
       out.println("Connection started from, " + client.getLocalAddress());
       out.flush();
       while (true) {
           String recieve = in.readLine();
           System.out.println(recieve);

           BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
           String send = reader.readLine();
           out.println(send);
           out.flush();
       }
            } catch (Exception e) {
               System.out.println(e);
        }
   }

   public void stopConnection() {
       try {
       in.close();
       out.close();
       client.close();
    }
       catch (Exception e) {

        }
}   
}

This is the server class file:

package com.evolution.server;

import java.io.*;
import java.net.*;

public class Server {
private int port = 325;
private ServerSocket server;
private Socket client;
private PrintWriter out;
private BufferedReader in;

public static void main(String[] args) throws IOException {
    Server server = new Server();
    System.out.println("Start Up!");
    server.start(server.port);
}

public void start(int port) throws IOException  {
    server = new ServerSocket(port);
    try {
        while (true) { //always runs unless break;
            client = server.accept();
               out = new PrintWriter(client.getOutputStream(), true);
                in = new BufferedReader(new 
InputStreamReader(client.getInputStream()));
                //out - send output 

                String inputLine;
                while ((inputLine = in.readLine()) != null) {
                    if (inputLine.equalsIgnoreCase("shutdown"))
                        stop();
                    System.out.println(inputLine);
                }
        }
    }   
    finally { //runs no matter what after try {}
        server.close();
            }
    }
public void stop() {
    try {
        in.close();
        out.close();
        client.close();
        server.close();
        System.exit(0);
    }
   catch (Exception e) {  
   }
}
}

If you have any possible solutions please let me know.

Your stop() method will skip all remaining steps on first exception. You should wrap each .close() call in its own try..catch block, or write a function to close InputStream/OutputStream/Socket. — KC Wong, Aug 14 '18 at 03:23

score 1 · Accepted Answer · edited Aug 13 '18 at 23:48

1

The line String recieve = in.readLine(); on the client side will block (BufferedReader readLine() blocks). Since the server isn't sending more lines, your code is stuck there.

Removing this line allows you to send messages from the client to the server.

edited Aug 13 '18 at 23:48

Bhargav Rao

50,140
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answered Aug 13 '18 at 22:57

Roy Shahaf

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out.println(); not working Java SocketServer

1 Answers1