Java 文件上传与下载

时间:2022-05-28 谷哥的小弟人气:0

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;
}

在这里插入图片描述

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());
		}
	}

}

在这里插入图片描述

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());
		}
	}

}

在这里插入图片描述

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());
		}

	}

}

在这里插入图片描述

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());
		}
	}

}

在这里插入图片描述

加载全部内容