springboot 导入excel和下载excel模版

下载文件模板使用 ClassPathResource resource = new ClassPathResource(fileName); 读取文件模板

1、导入和下载模版

/**
     * 导入excel
     *
     * @param file excel文件
     * @return 导入结果
     */
    @PostMapping("/importExcel")
    public Result importExcel(@RequestParam("file") MultipartFile file) {

        if (file.isEmpty()) {
            return ResultDataUtil.error("文件不能为空");
        }
        
        // 获取文件名，带后缀
        String fileName = file.getOriginalFilename();
        // 获取文件后缀
        String suffix = fileName.substring(fileName.lastIndexOf("."));

        File excelFile = null;
        try {
            excelFile = File.createTempFile(file.getName(), suffix);
            FileUtils.copyInputStreamToFile(file.getInputStream(), excelFile);
            String mimeType = FileUtil.getMimeType(excelFile.getPath());
            // excel 类型匹配
            boolean anyMatch = Arrays.stream(GlobalConstant.MIMETYPE_EXCEL).anyMatch(x -> x.equalsIgnoreCase(mimeType));
            if (anyMatch) {
                log.info("开始解析excel");
                ExcelReadListener<T> excelListener = new ExcelReadListener();
                // 文件类型正确，开始解析excel
                EasyExcelUtils.read(file.getInputStream(), T.class, excelListener);
                // 获取表数据
                List<T> excelDataList = excelListener.getDatas();
                log.info("excel解析完成，开始处理数据");
                
                return ResultDataUtil.success();
            }
            return ResultDataUtil.error("文件类型错误");
        } catch (IOException e) {
            log.error(e.getMessage(), e);
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        } finally {
            // 程序结束时，删除临时文件
            if (excelFile.exists()) {
                excelFile.delete();
            }
        }
        return ResultDataUtil.error("上传失败");
    }

    /**
     * 下载模板
     */
    @GetMapping("/downTemplate")
    public void downApiDoc(HttpServletRequest request, HttpServletResponse response) {

        BufferedInputStream inputStream = null;
        OutputStream outs = null;
        String fileName = "doc/API_interface.docx";
        try {
            ClassPathResource resource = new ClassPathResource(fileName);
            if (resource.exists()) {
                outs = response.getOutputStream();
                // 文件存在才能下载
                response.setContentType("application/octet-stream");
                response.setHeader("content-type", "application/octet-stream");
                // 设置文件名
                response.setHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(fileName, "UTF-8"));

                inputStream = new BufferedInputStream(resource.getInputStream());
                byte[] buffer = new byte[1024];
                while ((inputStream.read(buffer)) > 0) {
                    outs.write(buffer);
                    outs.flush();
                }
            } else {
                log.error("模板 [{}] 不存在", fileName);
            }
        } catch (IOException e) {
            log.error(e.getMessage(), e);
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outs != null) {
                try {
                    outs.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

2、添加 pom.xml 配置，处理导出模版乱码问题

        <resources>
			<resource>
				<directory>src/main/resources</directory>
				<filtering>true</filtering>
				<excludes>
					<exclude>**/*.xlsx</exclude>
					<exclude>**/*.xls</exclude>
				</excludes>
			</resource>
			<resource>
				<directory>src/main/resources</directory>
				<filtering>false</filtering>
				<includes>
					<include>**/*.xlsx</include>
					<include>**/*.xls</include>
				</includes>
			</resource>
		</resources>