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  • EasyExcel工具类,使用示例

     工具类:

     1、ExcelUtil.java

    public class ExcelUtil<T> {
    
        /***
         * 读取Excel方法
         */
        public static <T extends BaseRowModel> ArrayList<T> readExcel(MultipartFile excel, Class<T> clazz) {
            try {
                InputStream in = new BufferedInputStream(excel.getInputStream());
                GeneralExcelListener<T> listener = new GeneralExcelListener<>();
                ExcelReader excelReader = new ExcelReader(in, ExcelTypeEnum.XLS, listener);
                excelReader.read(new Sheet(1, 1, clazz));
                return listener.getSuccessDatas();
    
            } catch (Exception e) {
    
                return new ArrayList<T>();
            }
    
        }
    
    
        /**
         * 导出 Excel :一个 sheet,带表头
         *
         * @param response  HttpServletResponse
         * @param list      数据 list,每个元素为一个 BaseRowModel
         * @param fileName  导出的文件名
         * @param sheetName 导入文件的 sheet 名
         * @param object    映射实体类,Excel 模型
         */
        public static void writeExcel(HttpServletResponse response, List<? extends BaseRowModel> list,
                                      String fileName, String sheetName, BaseRowModel object) {
            ExcelWriter writer = new ExcelWriter(getOutputStream(fileName, response), ExcelTypeEnum.XLSX);
            Sheet sheet = new Sheet(1, 0, object.getClass());
            sheet.setSheetName(sheetName);
            writer.write(list, sheet);
            writer.finish();
    
        }
    
    
    
    
        /**
         * 导出文件时为Writer生成OutputStream
         */
        private static OutputStream getOutputStream(String fileName, HttpServletResponse response) {
            try {
                return response.getOutputStream();
            } catch (IOException e) {
                throw new RuntimeException("导出文件时为Writer生成OutputStream失败!");
            }
        }
    
        /**
         * 返回 ExcelReader
         *
         * @param excel         需要解析的 Excel 文件
         * @param excelListener new ExcelListener()
         */
        private static ExcelReader getReader(MultipartFile excel,
                                             ExcelListener excelListener) {
            String filename = excel.getOriginalFilename();
            if (filename == null || (!filename.toLowerCase().endsWith(".xls") && !filename.toLowerCase().endsWith(".xlsx"))) {
                throw new RuntimeException("文件格式错误!");
            }
            InputStream inputStream;
            try {
                inputStream = new BufferedInputStream(excel.getInputStream());
                return new ExcelReader(inputStream, null, excelListener, false);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
    }
    

      

    2、GeneralExcelListener.java

    /**
     * 解析Excel数据,返回数据的类
     **/
    
    
    public class GeneralExcelListener<T> extends AnalysisEventListener<T> {
    
        private final Logger logger = LoggerFactory.getLogger(this.getClass());
    
    
        //自定义用于暂时存储data。
        //可以通过实例获取该值
        private ArrayList<T> successDatas = new ArrayList<>();
        private ArrayList<T> errorDatas = new ArrayList<>();
    
        public GeneralExcelListener() {
    
        }
    
        @Override
        public void invoke(T o, AnalysisContext analysisContext) {
    
            successDatas.add(o);
        }
    
        @Override
        public void doAfterAllAnalysed(AnalysisContext context) {
    
        }
    
        public ArrayList<T> getErrorDatas() {
            return errorDatas;
        }
    
        public ArrayList<T> getSuccessDatas() {
            return successDatas;
        }
    
    
    }
    

      

    示例:

    Controller层代码

    1、导入示例

    @PostMapping(value = "/import")
    public ModelAndView import(@RequestParam(value = "file", required = true) MultipartFile file) {
    
    	ModelAndView mv = new ModelAndView();
    	//一行代码即可获取解析得到的Excel中的数据
    	List<Test> datas = ExcelUtil.readExcel(file, Test.class);
    	//然后对获取的数据,在service层进行业务处理
    	ResultMsg result = provShareConfigService.insertList(datas);
    	return mv;
    }
    

      

     2、导出示例

    @PostMapping(value = "/export")
    public void export(HttpServletRequest request, HttpServletResponse response, @RequestBody JSONObject ob) {
    	//前端传来的参数
    	String date = ob.getString("date");
    	String fileName = "退赔导出";
    	String sheetName = "sheet1";
    	//从数据库得到的list集合
    	List<Test> list = testService.selectAll(date);
    	//一行代码即可导出
    	ExcelUtil.writeExcel(response, list, fileName, sheetName, new Test());
    }
    

      

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  • 原文地址:https://www.cnblogs.com/Donnnnnn/p/12809668.html
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