Thread: Server and client help

I've been learning network IO recently, and made a server and client pair. The server can accept multiple clients, but when I write to the server from a client it prints it back to only the client that sent it.

Code:

import java.io.IOException;
import java.net.ServerSocket;

public class Server {
	
	public static void main(String[] args) throws IOException {
		ServerSocket s = null;
		boolean listening = true;
		try {
			s = new ServerSocket(5555);
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		while(listening)
			new ServerThread(s.accept()).start();
		
	}

}

Code:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class ServerThread extends Thread {

	private Socket sock = null;

	public ServerThread(Socket socket) {
		super("Server Thread");
		this.sock = socket;
	}

	public void run() {
		
		PrintWriter out = null;
		BufferedReader in = null;

		try {
			out = new PrintWriter(sock.getOutputStream(), true);
			in = new BufferedReader(new InputStreamReader(sock.getInputStream()));
			
			String input;
			
			while((input = in.readLine()) != null) {
				System.out.println(input);
				out.println(input);
			}
			
			in.close();
			out.close();
			sock.close();
			
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}

}

Code:

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 Client {

	public static void main(String[] args) throws IOException {
		Socket sock = null;
		PrintWriter out = null;
		BufferedReader in = null;

		try {
			sock = new Socket("127.0.0.1", 5555);
			out = new PrintWriter(sock.getOutputStream(), true);
			in = new BufferedReader(
					new InputStreamReader(sock.getInputStream()));
		} catch (UnknownHostException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		BufferedReader stdIn = new BufferedReader(new InputStreamReader(
				System.in));
		String userInput;
		
		
		while ((userInput = stdIn.readLine()) != null) {	
			out.println(userInput);
			System.out.println(in.readLine());
		}

		out.close();
		in.close();
		sock.close();
	}

}