1.7UDP
发短信：不用连接，需要对方的地址
发送端：
package com.zishi.lesson3;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
//不需要来凝结服务器
public class UdpClientDemo01 {
public static void main(String[] args) throws Exception {
//1.建立一个Socket
DatagramSocket socket = new DatagramSocket();
//2.建个包
String msg = "你好啊，服务器";
InetAddress localhost = InetAddress.getByName("localhost"); //发送给谁
int port = 9090;
//参数：数据，数据起始长度，发生给谁，
DatagramPacket packet = new DatagramPacket(msg.getBytes(), 0, msg.getBytes().length, localhost, port);
//3.发生包
socket.send(packet);
//4.关闭流
socket.close();
}
}
接收端：
package com.zishi.lesson3;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
//还是要等待客户端的连接
public class UdpServerDemo01 {
public static void main(String[] args) throws Exception{
//开放端口
DatagramSocket socket = new DatagramSocket(9090);
//接收数据包
byte[] buffer = new byte[1024];
DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length);
socket.receive(packet);//阻塞接收
System.out.println(packet.getAddress().getHostAddress());
System.out.println(new String(packet.getData(),0,packet.getLength()));
//关闭连接
socket.close();
}
}
UDP聊天实现：循环发送
发送端：
package com.zishi.chat;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
public class UdpSenderDemo01 {
public static void main(String[] args) throws Exception{
DatagramSocket socket = new DatagramSocket(8888);
//准备数据：控制台读取System.in
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
while(true){
String data = reader.readLine();
byte[] datas = data.getBytes();
DatagramPacket packet = new DatagramPacket(datas, 0, datas.length, new InetSocketAddress("localhost", 6666));
socket.send(packet);
if (data.equals("bye")){
break;
}
}
socket.close();
}
}
接收端：
package com.zishi.chat;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
public class UdpReceiveDemo01 {
public static void main(String[] args) throws Exception{
DatagramSocket socket = new DatagramSocket(6666);
while (true){
//准备接收baoguo
byte[] container = new byte[1024];
DatagramPacket packet = new DatagramPacket(container, 0, container.length);
socket.receive(packet);//阻塞式接收
//断开连接 bye
byte[] data = packet.getData();
String recevieData = new String(data, 0, data.length);
System.out.println(recevieData);
if (recevieData.equals("bye")){
break;
}
}
}
}
多线程聊天：
发送端：
package com.zishi.chat;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;
public class TalkSend implements Runnable{
DatagramSocket socket = null;
BufferedReader reader = null;
private int formPort;
private String toIP;
private int toPort;
public TalkSend(int formPort, String toIP, int toPort) {
this.formPort = formPort;
this.toIP = toIP;
this.toPort = toPort;
try {
socket = new DatagramSocket(formPort);
reader = new BufferedReader(new InputStreamReader(System.in));
} catch (SocketException e) {
e.printStackTrace();
}
}
@Override
public void run() {
while(true){
try {
String data = reader.readLine();
byte[] datas = data.getBytes();
DatagramPacket packet = new DatagramPacket(datas, 0, datas.length, new InetSocketAddress(this.toIP, this.toPort));
socket.send(packet);
if (data.equals("bye")){
break;
}
} catch (IOException e) {
e.printStackTrace();
}
}
socket.close();
}
}
接收端：
package com.zishi.chat;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
public class TalkReceive implements Runnable{
DatagramSocket socket = null;
private int port;
private String msgForm;
public TalkReceive(int port,String msgForm) {
this.port = port;
this.msgForm = msgForm;
try {
socket = new DatagramSocket(port);
} catch (SocketException e) {
e.printStackTrace();
}
}
@Override
public void run() {
while (true){
try {
//准备接收包裹
byte[] container = new byte[1024];
DatagramPacket packet = new DatagramPacket(container, 0, container.length);
socket.receive(packet);//阻塞式接收
//断开连接 bye
byte[] data = packet.getData();
String recevieData = new String(data, 0, data.length);
System.out.println(msgForm+":"+recevieData);
if (recevieData.equals("bye")){
break;
}
} catch (IOException e) {
e.printStackTrace();
}
}
socket.close();
}
}
学生：
package com.zishi.chat;
public class TalkStudent {
public static void main(String[] args) {
//开启两个线程
new Thread(new TalkSend(7777,"localhost",9999)).start();
new Thread(new TalkReceive(8888,"老师")).start();
}
}
老师：
package com.zishi.chat;
public class TalkTeacher {
public static void main(String[] args) {
new Thread(new TalkSend(5556,"localhost",8888)).start();
new Thread(new TalkReceive(9999,"学生")).start();
}
}