EasyExcel导入导出

一，工具类

 
import cn.hutool.json.JSONUtil;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.read.listener.PageReadListener;
import com.alibaba.excel.util.MapUtils;
import com.alibaba.excel.write.style.column.LongestMatchColumnWidthStyleStrategy;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.List;
import java.util.Map;
 
public class ExcelUtils <T> {
 
 
    /**
     * 文件下载并且失败的时候返回json（默认失败了会返回一个有部分数据的Excel）
     *
     * @since 2.1.1
     */
    public static <T> void excelDownload(HttpServletResponse response, String fileName, Class clazz, List<T> data) throws IOException {
        // 这里注意 有同学反应使用swagger 会导致各种问题，请直接用浏览器或者用postman
        try {
            response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
            response.setCharacterEncoding("utf-8");
            // 这里URLEncoder.encode可以防止中文乱码 当然和easyexcel没有关系
            response.setHeader("Content-disposition","attachment;filename*=utf-8''"+ URLEncoder.encode(fileName,"UTF-8").replaceAll("\\+","%20")+".xlsx");
            // LongestMatchColumnWidthStyleStrategy 自动调节单元格宽度策略
            EasyExcel.write(response.getOutputStream(),clazz).autoCloseStream(Boolean.FALSE).registerWriteHandler(new LongestMatchColumnWidthStyleStrategy()).sheet(fileName).doWrite(data);
        } catch (Exception e) {
            // 重置response
            response.reset();
            response.setContentType("application/json");
            response.setCharacterEncoding("utf-8");
            Map<String, String> map = MapUtils.newHashMap();
            map.put("status", "failure");
            map.put("message", "下载文件失败" + e.getMessage());
            response.getWriter().println(JSONUtil.toJsonStr(map));
        }
    }
 
 
    public static <T> void excelRead(MultipartFile excel, Class clazz , List<T> list) throws IOException {
        // 这里默认每次会读取100条数据 然后返回过来 直接调用使用数据就行
        // 具体需要返回多少行可以在`PageReadListener`的构造函数设置
        EasyExcel.read(excel.getInputStream(), clazz, new PageReadListener<T>(dataList -> {
            list.addAll(dataList);
        })).sheet().doRead();
    }
}

二，接口

        1，下载模板接口

              a,  模板类

@Data
@EqualsAndHashCode
public class ParkingBerthTemplateVO{
 
    @ExcelProperty(value = "停车场名称*",index = 0)
    private String parkingName;
 
    @ExcelProperty(value = "泊位编码*",index = 1)
    private String berthCode;
 
    @ExcelProperty(value = "设备编码*",index = 2)
    private String deviceCode;
 
}

             b,   接口

        @ApiOperation(value = "下载导入模板", notes = "下载导入模板")
        @GetMapping("template")
        public void downloadTemplate(HttpServletResponse response) throws IOException {
                String fileName = "导入模板";
                ExcelUtils.excelDownload(response, fileName, ParkingBerthTemplateVO.class, null);
        }

        2，导入接口                

        @ApiOperation(value = "导入", notes = "导入")
        @PostMapping("import")
        public Result<Boolean> berthImport(MultipartFile excel ) throws IOException {
 
                List<ParkingBerthTemplateVO> voList = new ArrayList<>();
                ExcelUtils.excelRead(excel,ParkingBerthTemplateVO.class, voList);
 
                Assert.isFalse(CollectionUtil.isEmpty(voList), "文件不能为空");
 
                 // 保存逻辑
               // parkingBerthService.berthImport(voList);
 
                return Result.ok();
        }

        3，导出接口

                a,导出vo类

 
/**
 * 停车订单
 */
@Data
@SuperBuilder
@NoArgsConstructor
@Accessors(chain = true)
@ExcelIgnoreUnannotated
public class OrderParkingExportDTO {
 
    @ColumnWidth(10)
    @ExcelProperty(value = "ID" ,index = 0)
    private Long id;
    
    @ExcelProperty(value = "供应商ID",index = 1)
    private Long tenantId;
 
//    @ColumnWidth(100)
    @ExcelProperty(value = "订单号",index = 2)
    private String orderCode;
 
    @ExcelProperty(value = "停车场ID",index = 3)
    private Long parkingId;
 
    @ExcelProperty(value = "停车场名称",index = 4 )
    private String parkingName;
 
    @ExcelProperty(value = "客户ID",index = 5 )
    private Long customerId;
 
    @ExcelProperty(value = "无牌/有牌",index = 6 )
    private String hasPlateNoString;
 
    @ExcelProperty(value = "车牌",index = 7 )
    private String plateNo;
 
    private PlateColor plateColor;
    @ExcelProperty(value = "车牌颜色",index = 8 )
    private String plateColorString;
 
    public void dataProcessor(){
        if(hasPlateNo!= null){
            hasPlateNoString = hasPlateNo == true ? "有牌" : "无牌";
        }
        if(plateColor!= null){
            plateColorString = plateColor.getDesc();
        }
    }
 
}

               b, 接口

        @ApiOperation(value = "列表导出", notes = "列表导出")
        @PostMapping("download")
        public void download(HttpServletResponse response,@RequestBody OrderParkingQueryVO vo, @ApiIgnore LoginSysUser loginSysUser) throws IOException {
 
                OrderParkingQueryDTO dto = OrderParkingConverter.INSTANCE.orderParking(vo, loginSysUser);
                List<OrderParking> list = orderParkingService.list(dto);
                List<OrderParkingExportDTO> data =  OrderParkingConverter.INSTANCE.entityToExportDto(list);
                data.forEach(item -> item.dataProcessor());
                String fileName = "列表导出";
                ExcelUtils.excelDownload(response,fileName,OrderParkingExportDTO.class,data);
        }