Echo

package kr.co.smu.network;

import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.io.PrintWriter;

import java.net.Socket;

public class EchoClient {

public static void main(String[] args) {

try{

Socket socket = new Socket("127.0.0.1", 10001);

BufferedReader keyboard = 

new BufferedReader(new InputStreamReader(System.in));

BufferedReader in = 

new BufferedReader(

new InputStreamReader(socket.getInputStream()));

PrintWriter out = new PrintWriter(socket.getOutputStream());

String line = null;

while((line = keyboard.readLine())!= null){

if(line.equals("quit"))

break;

out.println(line);

out.flush();

String echo = in.readLine();

System.out.println("서버가 보낸 문자열 : "+echo);

}

out.close();

in.close();

socket.close();

}catch(Exception e){

e.printStackTrace();

}

}

}

package kr.co.smu.network;

import java.io.BufferedReader;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.PrintWriter;

import java.net.ServerSocket;

import java.net.Socket;

public class EchoServer {

public static void main(String[] args) {

try{

ServerSocket server = new ServerSocket(10001);

System.out.println("접속 대기중!!");

Socket scoket = server.accept();

String host = scoket.getInetAddress().getHostAddress();

System.out.println(host+"로 부터 접속함!!");

InputStream in = scoket.getInputStream();

OutputStream out = scoket.getOutputStream();

BufferedReader br = 

new BufferedReader(new InputStreamReader(in));

PrintWriter pw = new PrintWriter(out);

String line = null;

while((line = br.readLine()) != null){

System.out.println("클라이언트가 보낸 문자열 : "+ line);

pw.println(line);

pw.flush();

}

pw.close();

br.close();

scoket.close();

}catch(Exception e){

e.printStackTrace();

}

}

}