import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.IOException;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.net.ServerSocket;import java.net.Socket;import java.util.Scanner;public class Server_1 {  public static void main(String[] args) {    InputStreamReader isr;    BufferedReader br;    OutputStreamWriter osw;    BufferedWriter bw;    String str;    Scanner in = new Scanner(System.in);    try {      ServerSocket server = new ServerSocket(4444);// 在本機的4444端口開放Server      Socket socket = server.accept();// 只要產生連接，socket便可以代表所連接的那個物體，同時這個server.accept()只有產生了連接才會進行下一步操作。      System.out.println(socket.getInetAddress());// 輸出連接者的IP。      System.out.println("建立了一個連接！");      while (true) {        isr = new InputStreamReader(socket.getInputStream());        br = new BufferedReader(isr);        System.out.println(socket.getInetAddress() + ":" + br.readLine());        osw = new OutputStreamWriter(socket.getOutputStream());        bw = new BufferedWriter(osw);        System.out.print("回復:");        str = in.nextLine();        bw.write(str + "/n");        bw.flush();      }    } catch (IOException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }  }}

import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.IOException;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.net.ServerSocket;import java.net.Socket;import java.util.Scanner;public class Client_1 {  public static void main(String[] args) {    InputStreamReader isr;    BufferedReader br;    OutputStreamWriter osw;    BufferedWriter bw;    String str;    Scanner in = new Scanner(System.in);    try {      Socket socket = new Socket("localhost", 4444);//     System.out.println(socket.getInetAddress());// 輸出連接者的IP。      System.out.println("成功連接服務器");      while (true) {        osw = new OutputStreamWriter(socket.getOutputStream());        bw = new BufferedWriter(osw);        System.out.print("回復:");        str = in.nextLine();        bw.write(str + "/n");        bw.flush();        isr = new InputStreamReader(socket.getInputStream());        br = new BufferedReader(isr);        System.out.println(socket.getInetAddress() + ":" + br.readLine());      }    } catch (IOException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }  }}