JAVA基础（UDP传输）
1，UDP传输
【1】发送Send
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创建DatagramSocket, 随机端口号
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创建DatagramPacket, 指定数据, 长度, 地址, 端口
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使用DatagramSocket发送DatagramPacket
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关闭DatagramSocket
【2】接收Receive
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创建DatagramSocket, 指定端口号
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创建DatagramPacket, 指定数组, 长度
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使用DatagramSocket接收DatagramPacket
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关闭DatagramSocket
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从DatagramPacket中获取数据
【3】接收方获取ip和端口号
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String ip = packet.getAddress().getHostAddress();
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int port = packet.getPort();
接收：
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
public class Demo1_Receive {
/**
** 2.接收Receive
* 创建DatagramSocket, 指定端口号
* 创建DatagramPacket, 指定数组, 长度
* 使用DatagramSocket接收DatagramPacket
* 关闭DatagramSocket
* 从DatagramPacket中获取数据
* @throws Exception
*/
public static void main(String[] args) throws Exception {
DatagramSocket socket = new DatagramSocket(6666); //创建Socket相当于创建码头
DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);//创建Packet相当于创建集装箱
socket.receive(packet); //接货,接收数据
byte[] arr = packet.getData(); //获取数据
int len = packet.getLength(); //获取有效的字节个数
System.out.println(new String(arr,0,len));
socket.close();
}
}
发送：
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
public class Demo1_Send {
/**
* * 1.发送Send
* 创建DatagramSocket, 随机端口号
* 创建DatagramPacket, 指定数据, 长度, 地址, 端口
* 使用DatagramSocket发送DatagramPacket
* 关闭DatagramSocket
* @throws SocketException
* @throws UnknownHostException
*/
public static void main(String[] args) throws Exception {
String str = "what are you 弄啥呢?";
DatagramSocket socket = new DatagramSocket(); //创建Socket相当于创建码头
DatagramPacket packet = //创建Packet相当于集装箱
new DatagramPacket(str.getBytes(), str.getBytes().length, InetAddress.getByName("127.0.0.1"), 6666);
socket.send(packet); //发货,将数据发出去
socket.close(); //关闭码头
}
}
2，UDP传输优化
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接收端Receive
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
public class Demo2_Receive {
/**
** 2.接收Receive
* 创建DatagramSocket, 指定端口号
* 创建DatagramPacket, 指定数组, 长度
* 使用DatagramSocket接收DatagramPacket
* 关闭DatagramSocket
* 从DatagramPacket中获取数据
* @throws Exception
*/
public static void main(String[] args) throws Exception {
DatagramSocket socket = new DatagramSocket(6666); //创建Socket相当于创建码头
DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);//创建Packet相当于创建集装箱
while(true) {
socket.receive(packet); //接货,接收数据
byte[] arr = packet.getData(); //获取数据
int len = packet.getLength(); //获取有效的字节个数
String ip = packet.getAddress().getHostAddress(); //获取ip地址
int port = packet.getPort(); //获取端口号
System.out.println(ip + ":" + port + ":" + new String(arr,0,len));
}
}
}
发送端Send
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Scanner;
public class Demo2_Send {
/**
* * 1.发送Send
* 创建DatagramSocket, 随机端口号
* 创建DatagramPacket, 指定数据, 长度, 地址, 端口
* 使用DatagramSocket发送DatagramPacket
* 关闭DatagramSocket
* @throws SocketException
* @throws UnknownHostException
*/
public static void main(String[] args) throws Exception {
Scanner sc = new Scanner(System.in); //创建键盘录入对象
DatagramSocket socket = new DatagramSocket(); //创建Socket相当于创建码头
while(true) {
String line = sc.nextLine(); //获取键盘录入的字符串
if("quit".equals(line)) {
break;
}
DatagramPacket packet = //创建Packet相当于集装箱
new DatagramPacket(line.getBytes(), line.getBytes().length, InetAddress.getByName("127.0.0.1"), 6666);
socket.send(packet); //发货,将数据发出去
}
socket.close(); //关闭码头
}
}
2，UDP传输多线程)
-
发送和接收在一个窗口完成
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Scanner;
public class Demo3_MoreThread {
/**
* @param args
*/
public static void main(String[] args) {
new Receive().start();
new Send().start();
}
}
class Receive extends Thread {
public void run() {
try {
DatagramSocket socket = new DatagramSocket(6666); //创建Socket相当于创建码头
DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);//创建Packet相当于创建集装箱
while(true) {
socket.receive(packet); //接货,接收数据
byte[] arr = packet.getData(); //获取数据
int len = packet.getLength(); //获取有效的字节个数
String ip = packet.getAddress().getHostAddress(); //获取ip地址
int port = packet.getPort(); //获取端口号
System.out.println(ip + ":" + port + ":" + new String(arr,0,len));
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
class Send extends Thread {
public void run() {
try {
Scanner sc = new Scanner(System.in); //创建键盘录入对象
DatagramSocket socket = new DatagramSocket(); //创建Socket相当于创建码头
while(true) {
String line = sc.nextLine(); //获取键盘录入的字符串
if("quit".equals(line)) {
break;
}
DatagramPacket packet = //创建Packet相当于集装箱
new DatagramPacket(line.getBytes(), line.getBytes().length, InetAddress.getByName("127.0.0.1"), 6666);
socket.send(packet); //发货,将数据发出去
}
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}