<dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>3.0.2</version>
        </dependency>

    /**
     * The easiest way to read Excel file using EasyExcel toolkit
     *
     * <p>
     *     1. Create an entity object, such as {@link DemoData}, each property of the entity object corresponds to a specific field in any row of Excel.
     *     2. When reading each row of an Excel file, create a callback listener for the corresponding row. Refer to{@link DemoDataListener}
     *     3. Invoke the read function
     * </p>
     */
    @Test
    public void simpleRead() {
        String fileName = TestFileUtil.getPath() + "demo" + File.separator + "demo.xlsx";
        // Specify which entity object class to use to read the Excel content. The file stream will close automatically after reading the first sheet of Excel.
        EasyExcel.read(fileName, DemoData.class, new DemoDataListener()).sheet().doRead();
    }

    /**
     * The easiest way to write Excel file using EasyExcel toolkit
     *
     * <p>
     *     1. Create an entity object, refer to{@link com.alibaba.easyexcel.test.demo.write.DemoData}. 
     *        Each property of the entity object corresponds to a specific field of Excel
     *     2. Invoke write function
     * </p>
     */
    @Test
    public void simpleWrite() {
        String fileName = TestFileUtil.getPath() + "write" + System.currentTimeMillis() + ".xlsx";
        // Specify which entity object class to use to write Excel, it will write to the first sheet of Excel with the name template. Then the file stream will be closed automatically.
        // With version 03, just pass in the excelType parameter
        EasyExcel.write(fileName, DemoData.class).sheet("template").doWrite(data());
    }

   /**
     * File downloading
     *
     * Note: returns an Excel with partial data if it fails
     *
     * <p>
     *  1. Create an entity object, refer to{@link DownloadData}. 
     *     Each property of the entity object corresponds to a specific field of Excel
     *  2. Specify the returned properties
     *  3. Invoke write function, then the OutputStream is automatically closed when it ends.
     * </p>
     */
    @GetMapping("download")
    public void download(HttpServletResponse response) throws IOException {
        // Using swagger may cause some problems, please use your browser directly or use postman to invoke this
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        // URLEncoder.encode function can prevent Chinese garbled code 
        String fileName = URLEncoder.encode("test", "UTF-8").replaceAll("\\+", "%20");
        response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
        EasyExcel.write(response.getOutputStream(), DownloadData.class).sheet("template").doWrite(data());
    }

    /**
     * File uploading
     *
     * <p>
     *     1. Create an entity object, refer to{@link UploadData}
     *        Each property of the entity object corresponds to a specific field of Excel
     *     2. When reading each row of an Excel file, create a callback listener for the corresponding row. Refer to{@link UploadDataListener}
     *     3. Invoke read function
     * </p>
     */
    @PostMapping("upload")
    @ResponseBody
    public String upload(MultipartFile file) throws IOException {
        EasyExcel.read(file.getInputStream(), UploadData.class, new UploadDataListener(uploadDAO)).sheet().doRead();
        return "success";
    }