Springboot文件上传

package com.example.springboot.controller;

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.util.IdUtil;
import cn.hutool.core.util.StrUtil;
import com.example.springboot.enity.Files;
import com.example.springboot.mapper.FileMapper;
import com.example.springboot.service.UserService;
import jakarta.annotation.Resource;
import jakarta.servlet.ServletOutputStream;
import jakarta.servlet.http.HttpServletResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import java.io.IOException;
import java.net.URLEncoder;

/**
 * 文件上传相关接口
 */
@RestController
@RequestMapping("/file")
public class FileController {

    @Autowired
    private UserService userService;


    //  将配置文件中的path读入
    @Value("${files.upload.path}")
    private String fileUploadPath;

    @Resource
    private FileMapper fileMapper;

    /**
     * 文件上传接口
     * @param file
     * @return
     * @throws IOException
     */

    @PostMapping("/upload")
    public String upload(MultipartFile file) throws IOException {
        System.out.println("===============fileUpload============");
        System.out.println("==========="+fileUploadPath);
        String originalFilename = file.getOriginalFilename();
        String type = FileUtil.extName(originalFilename);
        long size = file.getSize();
        // 先存储到磁盘
        File uploadParentFile = new File(fileUploadPath);
        // 判断配置的文件目录是否存在，若不存在则创建一个新的文件目录
        if(!uploadParentFile.exists()){
            uploadParentFile.mkdirs();
        }
        //  定义一个文件唯一的标识码
        String uuid = IdUtil.fastSimpleUUID();
        String fileUuid = uuid + StrUtil.DOT + type;
        File uploadFile = new File(fileUploadPath + fileUuid);
        //把获取到的文件存储到磁盘目录去
        file.transferTo(uploadFile);

        String url = "http://localhost:8080/file/" + fileUuid;
        // 存储数据库
        Files saveFile = new Files();
        saveFile.setName(originalFilename);
        saveFile.setType(type);
        saveFile.setSize(size/1024);
        saveFile.setUrl(url);
        fileMapper.insert(saveFile);
        return url;
    }

    /**
     * 文件下载接口   http://localhost:8080/file/{fileUUID}
     * @param fileUUID
     * @param response
     * @throws IOException
     */

    @GetMapping("/{fileUUID}")
    public void download(@PathVariable String fileUUID, HttpServletResponse response) throws IOException {
        System.out.println("============downloadFile===========");
        //根据文件的唯一标识码获取文件
        File uploadFile = new File(fileUploadPath + fileUUID);
        //  设置输出流的格式
        ServletOutputStream os = response.getOutputStream();
        response.addHeader("Content-Disposition","attachment;filename=" + URLEncoder.encode(fileUUID,"UTF-8"));
        response.setContentType("application/octet-stream");

        //读取文件的字节流
        os.write(FileUtil.readBytes(uploadFile));
        os.flush();
        os.close();
    }
}

通过localhost:8080/file/upload上传文件
通过localhost:8080/file/+文件序号 下载文件