TCP（Transmission Control Protocol 传输控制协议）是一种面向连接的、可靠的、基于字节流的传输层通信协议
UDP （User Datagram Protocol 用户数据报协议）是OSI（Open System Interconnection开放式系统互联） 参考模型中一种无连接的传输层协议，提供面向事务的简单不可靠信息传送服务
TCP与UDP基本区别
- 1.基于连接与无连接
- 2.TCP要求系统资源较多，UDP较少；
- 3.UDP程序结构较简单
- 4.流模式（TCP）与数据报模式(UDP);
- 5.TCP保证数据正确性，UDP可能丢包
- 6.TCP保证数据顺序，UDP不保证
一、Tcp协议通信
1、Server服务器端：
- a、创建ServerSocket对象，同时绑定监听端口
- b、通过accept()方法监听客户端的请求
- c、建立连接后，通过输入流读取客户端发送的请求信息
- d、通过输出流向客户端发送响应信息
- e、关闭相应资源
package com.yyx.test;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class TcpServerSocket {
public static void main(String[] args) {
ServerSocket serverSocket = null;
Socket socket = null;
InputStream inputStream = null;
OutputStream outputStream = null;
FileOutputStream fileOutputStream = null;
try {
// 创建一个ServerSocket的对象，通过构造器指明自身的端口号
serverSocket = new ServerSocket(9090);
// 服务端监听 调用其accept()方法，返回一个Socket的对象
socket = serverSocket.accept();
inputStream = socket.getInputStream();
String pathname = "F:" + File.separator + "target.jpg";
File file = new File(pathname);
fileOutputStream = new FileOutputStream(file);
/*
* 接收客户端发送文件，并保存到本地文件
*/
byte[] b = new byte[1024];
int len;
while ((len = inputStream.read(b)) != -1) {
fileOutputStream.write(b, 0, len);
}
String strInfo = "你发送的图片我已接收成功！";
outputStream = socket.getOutputStream();
outputStream.write(strInfo.getBytes());
} catch (Exception e) {
e.printStackTrace();
} finally {
// 关闭相应的流以及Socket、ServerSocket的对象
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fileOutputStream != null) {
try {
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (serverSocket != null) {
try {
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
2、Client客户端：
- a、创建Socket对象，指明需要连接的服务器的地址和端口号
- b、建立连接后，通过输出流向服务器端发送请求信息
- c、通过输入流获取服务器的响应信息
- d、关闭相应资源
package com.yyx.test;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
public class TcpClientSocket {
public static void main(String[] args) {
Socket socket = null;
OutputStream outputStream = null;
InputStream inputStream = null;
FileInputStream fileInputStream=null;
try {
// 创建一个Socket的对象，通过构造器指明服务端的IP地址，以及其接收程序的端口号
socket = new Socket(InetAddress.getByName("127.0.0.1"), 9090);
String pathname = "F:" + File.separator + "source.jpg";
File file = new File(pathname);
fileInputStream=new FileInputStream(file);
// getOutputStream()：发送数据，方法返回OutputStream的对象
outputStream = socket.getOutputStream();
byte[] b = new byte[1024];
int len;
while ((len = fileInputStream.read(b)) != -1) {
outputStream.write(b, 0, len);
}
// shutdownOutput():执行此方法，显式的告诉服务端发送完毕！
socket.shutdownOutput();
inputStream = socket.getInputStream();
byte[] bAnother = new byte[1024];
int lenAnother;
while ((lenAnother = inputStream.read(bAnother)) != -1) {
String str = new String(bAnother, 0, lenAnother);
System.out.print(str);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// 关闭相应的流和Socket对象,从后往前关闭
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fileInputStream != null) {
try {
fileInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
二、Udp协议通信
客户端
package com.yyx.test;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
public class UdpClientSocket {
public static void main(String[] args) {
DatagramSocket datagramSocket = null;
try {
datagramSocket = new DatagramSocket();
String str = "你好，我是要发送的数据";
byte[] b = str.getBytes();
/*
* 创建一个数据报：每一个数据报不能大于64k，都记录着数据信息，发送端的IP、端口号,以及要发送到 的接收端的IP、端口号
*/
DatagramPacket pack = new DatagramPacket(b, 0, b.length, InetAddress.getByName("127.0.0.1"), 9090);
datagramSocket.send(pack);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (datagramSocket != null) {
datagramSocket.close();
}
}
}
}
服务端
package com.yyx.test;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
public class UdpServerSocket {
public static void main(String[] args) {
DatagramSocket datagramSocket = null;
try {
datagramSocket = new DatagramSocket(9090);
byte[] b = new byte[1024];
DatagramPacket pack = new DatagramPacket(b, 0, b.length);
datagramSocket.receive(pack);
String str = new String(pack.getData(), 0, pack.getLength());
System.out.println(str);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (datagramSocket != null) {
datagramSocket.close();
}
}
}
}
原文地址：https://www.cnblogs.com/xianya/p/9216962.html
时间： 2024-08-08 22:08:34