文件上传下载工具类

文件上传下载工具类

文件下载，从服务器的目录上下载Excel模板文件
文件上传，把文件上传到服务器指定目录下，或者把文件上传到FastDFS或者OSS

import cn.hutool.core.date.DateUtil;
import cn.hutool.core.util.IdUtil;
import cn.hutool.core.util.StrUtil;
import cn.yto.safe.common.enums.FileTypeEnums;
import cn.yto.safe.common.enums.ResponseEnums;
import cn.yto.safe.model.base.JsonResponse;
import cn.yto.safe.model.entity.ExcelFile;
import cn.yto.safe.service.ExcelFileService;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.FileUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.net.URLEncoder;
import java.util.Date;

/**
 * <p>
 * 工具类方法
 * </p>
 *
 * @author yanyg
 * @date 2022/3/31 13:13
 */
@Slf4j
@RestController
@RequestMapping("/tool")
public class ToolController {

    @Value("${template.path:/opt/template/}")
    private String templatePath;
    @Value("${upload.path:/opt/upload/}")
    private String uploadPath;

    @Resource
    private ExcelFileService excelFileService;

    /**
     * <p>
     * 下载Excel模板
     * </p>
     */
    @GetMapping("/downloadTemplate")
    public void downloadTemplate(@RequestParam("fileType") String fileType,
                                 HttpServletResponse response) throws Exception {
        if (StrUtil.isBlank(fileType)) {
            throw new Exception("文件类型不能为空");
        }

        String fileName = FileTypeEnums.getDescriptionByCode(fileType);
        //获取要下载的文件全路径名
        String realPath = templatePath + fileName;

        //以流的形式下载文件
        InputStream fis = new BufferedInputStream(new FileInputStream(realPath));
        byte[] buffer = new byte[fis.available()];
        fis.read(buffer);
        fis.close();

        //清空response
        response.reset();
        //设置response响应头
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/octet-stream");
        response.setHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(fileName, "UTF-8"));

        OutputStream outputStream = new BufferedOutputStream(response.getOutputStream());
        outputStream.write(buffer);
        outputStream.flush();
        outputStream.close();

    }

    /**
     * <p>
     * 文件上传获取文件ID接口
     * </p>
     *
     * @param file
     * @return {@link JsonResponse}
     **/
    @PostMapping("/generateFileId")
    public JsonResponse fileTest(@RequestParam("file") MultipartFile file) throws IOException {
        if (file.isEmpty()) {
            return JsonResponse.fail(ResponseEnums.EXCEPTION_BUSINESS, "文件不能为空");
        }

        Date date = new Date();
        // 取年度
        int year = DateUtil.year(date);
        //获得月份，从0开始计数
        int month = DateUtil.month(date) + 1;
        String monthStr = String.valueOf(month);
        if (month < 10) {
            monthStr = "0" + month;
        }

        String dirPath = uploadPath + year + File.separator + monthStr;
        File dirFile = new File(dirPath);
        if (!dirFile.exists()) {
            // 创建文件夹(可创建多级)
            FileUtils.forceMkdir(dirFile);
        }

        //文件原名称
        String fileName = file.getOriginalFilename();
        //文件类型
        String type = fileName.substring(fileName.lastIndexOf("."));
        // 判断文件是否为 excel 文件
        if (".xlsx".equals(type) || ".xls".equals(type)) {
            String newFileName = IdUtil.simpleUUID() + fileName;
            String newFilePath = dirPath + File.separator + newFileName;
            // 文件复制
            file.transferTo(new File(newFilePath));

            ExcelFile excelFile = new ExcelFile();
            excelFile.setFileId(IdUtil.simpleUUID());
            excelFile.setFileName(newFileName);
            excelFile.setFilePath(newFilePath);
            excelFile.setFinishImport(false);
            int num = excelFileService.saveExcelFile(excelFile);
            log.info("文件ID：{},保存记录成功数：{}", excelFile.getFileId(), num);
            return JsonResponse.succcess(excelFile);
        }
        return JsonResponse.fail(ResponseEnums.EXCEPTION_BUSINESS, "不是Excel类型");
    }


}

推荐使用第三方sdk

 <!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
 <dependency>
     <groupId>commons-io</groupId>
     <artifactId>commons-io</artifactId>
     <version>2.11.0</version>
 </dependency>