网络编程
网络概述
IP地址
IP地址组成
IP命令
DNS
网络服务器
网络通信协议
基于TCP协议的Socket编程
import java.io.Serializable; public class User implements Serializable { private String name; private String pwd; public User() { } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd = pwd; } public User(String name, String pwd) { super(); this.name = name; this.pwd = pwd; } }
import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket; public class ServerLogin { public static void main(String[] args) { // 1、创建一个ServerSocket对象，指定端口号 try { ServerSocket serverSocket = new ServerSocket(8000); // 2、监听者客户端请求 Socket socket = serverSocket.accept(); // 3、打开流，处理用户请求 InputStream is = socket.getInputStream(); OutputStream os = socket.getOutputStream(); ObjectInputStream ois = new ObjectInputStream(is); User user; try { user = (User) ois.readObject(); System.out.println("我是服务器，客户端信息为：" + user.getName() + "，密码" + user.getPwd()); } catch (ClassNotFoundException e) { e.printStackTrace(); } socket.shutdownInput(); // 服务器给客户端一个响应 String info = "欢迎您，登录成功！"; os.write(info.getBytes()); // 4、关闭资源 ois.close(); os.close(); is.close(); socket.close(); serverSocket.close(); } catch (IOException e) { e.printStackTrace(); } } }
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.ObjectOutputStream; import java.io.OutputStream; import java.net.Socket; public class ClientLogin { public static void main(String[] args) { // 1、创建一个socket对象（指定服务器IP，端口号） try { Socket socket = new Socket("localhost", 8000); // 2、打开流，发送请求 OutputStream os = socket.getOutputStream(); InputStream is = socket.getInputStream(); User user = new User("TOM", "1234"); // 创建用来发送的对象 ObjectOutputStream oos = new ObjectOutputStream(os); oos.writeObject(user); socket.shutdownOutput(); // 接收服务器反馈 BufferedReader br = new BufferedReader(new InputStreamReader(is)); String info = ""; while ((info = br.readLine()) != null) { System.out.println("我是客户端，服务器的响应是：" + info); } // 3、关闭资源 oos.close(); is.close(); os.close(); socket.close(); } catch (IOException e) { e.printStackTrace(); } } }
多线程处理多请求
import java.io.IOException; import java.net.ServerSocket; import java.net.Socket; import cn.bdqn.xhd.socket2.LoginThread; public class ServerLogin { public static void main(String[] args) { // 1、创建一个ServerSocket对象，指定端口号 ServerSocket serverSocket = null; try { serverSocket = new ServerSocket(8000); // 持续监听 while (true) { Socket socket = serverSocket.accept(); LoginThread loginThread = new LoginThread(socket); loginThread.start(); // 启动线程，处理客户端请求 } } catch (IOException e) { e.printStackTrace(); } } }
import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.OutputStream; import java.net.Socket; import cn.bdqn.xhd.socket.User; public class LoginThread extends Thread { Socket socket = null; public LoginThread(Socket socket) { this.socket = socket; } // 处理用户请求 public void run() { try { // 3、打开流，处理用户请求 InputStream is = socket.getInputStream(); OutputStream os = socket.getOutputStream(); ObjectInputStream ois = new ObjectInputStream(is); User user; try { user = (User) ois.readObject(); System.out.println("我是服务器，客户端信息为：" + user.getName() + "，密码" + user.getPwd()); } catch (ClassNotFoundException e) { e.printStackTrace(); } socket.shutdownInput(); // 服务器给客户端一个响应 String info = "欢迎您，登录成功！"; os.write(info.getBytes()); // 4、关闭资源 ois.close(); os.close(); is.close(); socket.close(); } catch (IOException e) { e.printStackTrace(); } } }
基于UDP协议的网络编程
import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.InetAddress; import java.net.SocketException; import java.net.UnknownHostException; public class Send { public static void main(String[] args) { InetAddress ia = null; DatagramSocket ds = null; try { String mess = "你好，我想咨询一个问题。"; // 显示与本地对话框 System.out.println("我说：" + mess); // 获取本地主机地址 ia = InetAddress.getByName("localhost"); // 创建DatagramPacket对象，封装数据 DatagramPacket dp = new DatagramPacket(mess.getBytes(), mess.getBytes().length, ia, 8800); // 创建DatagramSocket对象，向服务器发送数据 ds = new DatagramSocket(); ds.send(dp); byte[] buf = new byte[1024]; DatagramPacket dpre = new DatagramPacket(buf, buf.length); ds.receive(dpre); // 显示接收到的信息 String reply = new String(dpre.getData(), 0, dpre.getLength()); System.out.println(dpre.getAddress().getHostAddress() + "说：" + reply); } catch (UnknownHostException e) { e.printStackTrace(); } catch (SocketException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭DatagramSocket对象 ds.close(); } } }
import java.io.IOException; import java.net.DatagramPacket; import java.net.DatagramSocket; import java.net.SocketAddress; import java.net.SocketException; public class Receive { public static void main(String[] args) { DatagramPacket dp = null; DatagramSocket ds = null; DatagramPacket dpto = null; try { // 创建DatagramPacket对象，用来准备接收数据包 byte[] buf = new byte[1024]; dp = new DatagramPacket(buf, buf.length); // 创建DatagramSocket对象，接收数据 ds = new DatagramSocket(8800); ds.receive(dp); // 显示接收到的信息 String mess = new String(dp.getData(), 0, dp.getLength()); System.out.println(dp.getAddress().getHostAddress() + "说：" + mess); String reply = "你好，我在，请咨询！"; // 显示与本地对话框 System.out.println("我说：" + reply); // 创建DatagramPacket对象，封装数据 SocketAddress sa = dp.getSocketAddress(); dpto = new DatagramPacket(reply.getBytes(), reply.getBytes().length, sa); ds.send(dpto); } catch (SocketException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭DatagramSocket对象 ds.close(); } } }
