利用Socket和IO流实现文件的上传与下载

Posted 2022-04-12 谷哥的小弟

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版权声明

• 本文原创作者：谷哥的小弟
• 作者博客地址：http://blog.csdn.net/lfdfhl

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背景概述

本文利用Socket编程和IO流技术实现文件的上传与下载。

核心技术

• 1、TCP
• 2、Socket
• 3、FileInputStream与FileOutputStream
• 4、DataInputStream与DataOutputStream
• 5、多线程

Config

package com.io14;
/**
 * 本文作者：谷哥的小弟 
 * 博客地址：http://blog.csdn.net/lfdfhl
 */
public class Config 
	public static final String ip = "localhost";
	public static final int port = 10088;

Client

package com.io14;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
/**
 * 本文作者：谷哥的小弟 
 * 博客地址：http://blog.csdn.net/lfdfhl
 */
public class Client 

	public static void main(String arg[]) 
		testDownload();
	

	public static void testUpload() 
		String filePath = "D:" + File.separator + "beauty.jpg";
		Client client = new Client();
		client.uploadFile(filePath);
	

	public static void testDownload() 
		Client client = new Client();
		client.downloadFile();
	

	public void uploadFile(String filePath) 
		try 
			// 创建待上传文件对象
			File file = new File(filePath);
			String fileName = file.getName();
			long fileLength = file.length();
			System.out.println("客户端待上传文件：" + fileName + "，其大小为：" + fileLength);

			// 创建FileInputStream
			FileInputStream fileInputStream = new FileInputStream(filePath);

			// 创建Socket对象
			Socket socket = new Socket(Config.ip, Config.port);
			// 从Socket获取OutputStream
			OutputStream outputStream = socket.getOutputStream();
			// 创建DataOutputStream
			DataOutputStream dataOutputStream = new DataOutputStream(outputStream);

			// 利用DataOutputStream写出文件名和文件大小
			dataOutputStream.writeUTF(fileName);
			dataOutputStream.writeLong(fileLength);
			dataOutputStream.flush();

			// IO流读写操作
			byte[] buf = new byte[1024 * 1];
			int len = 0;
			while ((len = fileInputStream.read(buf)) != -1) 
				dataOutputStream.write(buf, 0, len);
			

			// 释放资源
			dataOutputStream.flush();
			fileInputStream.close();
			socket.close();
		 catch (Exception e) 
			System.out.println(e.toString());
		
	

	public void downloadFile() 
		try 
			// 创建Socket对象
			Socket socket = new Socket(Config.ip, Config.port);
			// 从Socket获取InputStream
			InputStream inputStream = socket.getInputStream();
			// 创建DataInputStream对象
			DataInputStream dataInputStream = new DataInputStream(inputStream);

			// 获取下载文件的文件名和文件大小
			String fileName = dataInputStream.readUTF();
			long fileLength = dataInputStream.readLong();
			System.out.println("客户端下载文件：" + fileName + "，其大小为：" + fileLength);

			// 组拼文件保存路径
			String fileDir = "D:";
			String filePath = fileDir + File.separator + fileName;

			// 创建FileOutputStream对象
			FileOutputStream fileOutputStream = new FileOutputStream(filePath);

			// IO流读写操作
			byte[] buf = new byte[1024 * 1];
			int len = 0;
			while ((len = dataInputStream.read(buf)) != -1) 
				fileOutputStream.write(buf, 0, len);
			

			// 释放资源
			fileOutputStream.flush();
			fileOutputStream.close();
			dataInputStream.close();
			socket.close();
		 catch (Exception e) 
			System.out.println(e.toString());
		
	

Server

package com.io14;

import java.net.ServerSocket;
import java.net.Socket;
/**
 * 本文作者：谷哥的小弟 
 * 博客地址：http://blog.csdn.net/lfdfhl
 */
public class Server 
	public static void main(String arg[]) 
		testDownload();
	
	
	public static void testUpload() 
		Server server = new Server();
		server.handleUploadFile();
	
	
	public static void testDownload() 
		Server server = new Server();
		server.handleDownloadFile();
	

	public void handleUploadFile() 
		try 
			// 创建ServerSocket对象
			ServerSocket serverSocket = new ServerSocket(Config.port);
			while (true) 
				// 接收客户端连接请求
				Socket socket = serverSocket.accept();
				// 开启子线程处理文件上传
				UploadRunnableImpl uploadRunnableImpl = new UploadRunnableImpl(socket);
				Thread thread = new Thread(uploadRunnableImpl);
				thread.start();
			
		 catch (Exception e) 
			System.out.println(e.toString());
		

	

	public void handleDownloadFile() 
		try 
			// 创建ServerSocket对象
			ServerSocket serverSocket = new ServerSocket(Config.port);
			while (true) 
				// 接收客户端连接请求
				Socket socket = serverSocket.accept();
				// 开启子线程处理文件下载
				DownloadRunnableImpl downloadRunnableImpl = new DownloadRunnableImpl(socket);
				Thread thread = new Thread(downloadRunnableImpl);
				thread.start();
			
		 catch (Exception e) 
			System.out.println(e.toString());
		
	

UploadRunnableImpl

package com.io14;

import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.net.Socket;
/**
 * 本文作者：谷哥的小弟 
 * 博客地址：http://blog.csdn.net/lfdfhl
 */
public class UploadRunnableImpl implements Runnable 
	private Socket socket;
	
	public UploadRunnableImpl(Socket socket) 
		this.socket = socket;
	

	@Override
	public void run() 
		try 
			// 从Socket获取InputStream
			InputStream inputStream = socket.getInputStream();
			// 创建DataInputStream对象
			DataInputStream dataInputStream = new DataInputStream(inputStream);
			
			// 获取上传文件的文件名和文件大小
			String fileName = dataInputStream.readUTF();
			long fileLength = dataInputStream.readLong();
			System.out.println("服务端接收上传文件："+fileName+"，其大小为："+fileLength);
			
			// 组拼文件保存路径
			String fileDir = "E:";
			String filePath= fileDir + File.separator+fileName;
			
			// 创建FileOutputStream对象
			FileOutputStream fileOutputStream = new FileOutputStream(filePath);
			
			// IO流读写操作
			byte[] buf = new byte[1024*1];
			int len = 0;
			while ((len = dataInputStream.read(buf)) != -1) 
				fileOutputStream.write(buf, 0, len);
			
			
			// 释放资源
			fileOutputStream.flush();
			fileOutputStream.close();
			dataInputStream.close();
			socket.close();
		 catch (Exception e) 
			System.out.println(e.toString());
		

	

DownloadRunnableImpl

package com.io14;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.net.Socket;
/**
 * 本文作者：谷哥的小弟 
 * 博客地址：http://blog.csdn.net/lfdfhl
 */
public class DownloadRunnableImpl implements Runnable
	private Socket socket;
	
	public DownloadRunnableImpl(Socket socket) 
		this.socket = socket;
	

	@Override
	public void run() 
		try 
			// 创建待下载文件对象
			String filePath = "E:"+File.separator+"beauty.jpg";
			File file = new File(filePath);
			String fileName = file.getName();
			long fileLength = file.length();
			System.out.println("服务端待下载文件：" + fileName + "，其大小为：" + fileLength);

			// 创建FileInputStream
			FileInputStream fileInputStream = new FileInputStream(filePath);

			// 从Socket获取OutputStream
			OutputStream outputStream = socket.getOutputStream();
			// 创建DataOutputStream
			DataOutputStream dataOutputStream = new DataOutputStream(outputStream);

			// 利用DataOutputStream写出文件名和文件大小
			dataOutputStream.writeUTF(fileName);
			dataOutputStream.writeLong(fileLength);
			dataOutputStream.flush();

			// IO流读写操作
			byte[] buf = new byte[1024 * 1];
			int len = 0;
			while ((len = fileInputStream.read(buf)) != -1) 
				dataOutputStream.write(buf, 0, len);
			

			// 释放资源
			dataOutputStream.flush();
			fileInputStream.close();
			socket.close();
		 catch (Exception e) 
			System.out.println(e.toString());