SpringBoot实现导入导出Excel 基操

导入maven依赖

    cn.afterturn
    easypoi-spring-boot-starter
    4.4.0

简单导出

先手创建实体 Member 会员信息

@Data
@EqualsAndHashCode(callSuper = false)
public class Member {
    @Excel(name = "ID", width = 10)
    private Long id;
    @Excel(name = "用户名", width = 20, needMerge = true)
    private String username;
    private String password;
    @Excel(name = "昵称", width = 20, needMerge = true)
    private String nickname;
    @Excel(name = "出生日期", width = 20, format = "yyyy-MM-dd")
    private Date birthday;
    @Excel(name = "手机号", width = 20, needMerge = true, desensitizationRule = "3_4")
    private String phone;
    private String icon;
    @Excel(name = "性别", width = 10, replace = {"男_0", "女_1"})
    private Integer gender;
}

我们就可以看到EasyPoi的核心注解@Excel，通过在对象上添加@Excel注解，可以将对象信息直接导出到Excel中去，下面对注解中的属性做个介绍；
name：Excel中的列名；
width：指定列的宽度；
needMerge：是否需要纵向合并单元格；
format：当属性为时间类型时，设置时间的导出导出格式；
desensitizationRule：数据脱敏处理，3_4表示只显示字符串的前3位和后4位，其他为*号；
replace：对属性进行替换；
suffix：对数据添加后缀。

接下来我们在Controller中添加一个接口，用于导出会员列表到Excel，具体代码如下；

@Controller
@Api(tags = "EasyPoiController", description = "EasyPoi导入导出测试")
@RequestMapping("/easyPoi")
public class EasyPoiController {

    @ApiOperation(value = "导出会员列表Excel")
    
    @RequestMapping(value = "/exportMemberList", method = RequestMethod.GET)
    
    public void exportMemberList(ModelMap map,
                                 HttpServletRequest request,
                                 HttpServletResponse response) {
        List memberList = LocalJsonUtil.getListFromJson("json/members.json", Member.class);
        
        ExportParams params = new ExportParams("会员列表", "会员列表", ExcelType.XSSF);
        
        map.put(NormalExcelConstants.DATA_LIST, memberList);
        
        map.put(NormalExcelConstants.CLASS, Member.class);
        
        map.put(NormalExcelConstants.PARAMS, params);
        
        map.put(NormalExcelConstants.FILE_NAME, "memberList");
        
        PoibaseView.render(map, request, response, NormalExcelConstants.EASYPOI_EXCEL_VIEW);
    }
}

简单导入

在Controller中添加会员信息导入的接口，这里需要注意的是使用@RequestPart注解修饰文件上传参数，否则在Swagger中就没法显示上传按钮了；

@Controller
@Api(tags = "EasyPoiController", description = "EasyPoi导入导出测试")
@RequestMapping("/easyPoi")
public class EasyPoiController {

    @ApiOperation("从Excel导入会员列表")
    @RequestMapping(value = "/importMemberList", method = RequestMethod.POST)
    @ResponseBody
    public CommonResult importMemberList(@RequestPart("file") MultipartFile file) {
        
        importParams params = new importParams();
        
        params.setTitleRows(1);
        
        params.setHeadRows(1);
        
        try {
            List list = ExcelimportUtil.importExcel(
                    file.getInputStream(),
                    Member.class, params);
            
            return CommonResult.success(list);
        } catch (Exception e) {
           
            e.printStackTrace();
           
            return CommonResult.failed("导入失败！");
        }
    }
}

复杂导出

当然EasyPoi也可以实现更加复杂的Excel操作，比如导出一个嵌套了会员信息和商品信息的订单列表，下面我们来实现下！

@Data
@EqualsAndHashCode(callSuper = false)
public class Product {
    @Excel(name = "ID", width = 10)
    private Long id;
    @Excel(name = "商品SN", width = 20)
    private String productSn;
    @Excel(name = "商品名称", width = 20)
    private String name;
    @Excel(name = "商品副标题", width = 30)
    private String subTitle;
    @Excel(name = "品牌名称", width = 20)
    private String brandName;
    @Excel(name = "商品价格", width = 10)
    private BigDecimal price;
    @Excel(name = "购买数量", width = 10, suffix = "件")
    private Integer count;
}

然后添加订单对象Order，订单和会员是一对一关系，使用@ExcelEntity注解表示，订单和商品是一对多关系，使用@ExcelCollection注解表示，Order就是我们需要导出的嵌套订单数据；

@Data
@EqualsAndHashCode(callSuper = false)
public class Order {
    @Excel(name = "ID", width = 10,needMerge = true)
    private Long id;
    @Excel(name = "订单号", width = 20,needMerge = true)
    private String orderSn;
    @Excel(name = "创建时间", width = 20, format = "yyyy-MM-dd HH:mm:ss",needMerge = true)
    private Date createTime;
    @Excel(name = "收货地址", width = 20,needMerge = true )
    private String receiverAddress;
    @ExcelEntity(name = "会员信息")
    private Member member;
    @ExcelCollection(name = "商品列表")
    private List productList;
}

接下来在Controller中添加导出订单列表的接口，由于有些会员信息我们不需要导出，可以调用ExportParams中的setExclusions方法排除掉；

@Controller
@Api(tags = "EasyPoiController", description = "EasyPoi导入导出测试")
@RequestMapping("/easyPoi")
public class EasyPoiController {

    @ApiOperation(value = "导出订单列表Excel")
    @RequestMapping(value = "/exportOrderList", method = RequestMethod.GET)
    public void exportOrderList(ModelMap map,
                                HttpServletRequest request,
                                HttpServletResponse response) {
        
        List orderList = getOrderList();
       
        ExportParams params = new ExportParams("订单列表", "订单列表", ExcelType.XSSF);
        //导出时排除一些字段
       
        params.setExclusions(new String[]{"ID", "出生日期", "性别"});
       
        map.put(NormalExcelConstants.DATA_LIST, orderList);
      
        map.put(NormalExcelConstants.CLASS, Order.class);
      
        map.put(NormalExcelConstants.PARAMS, params);
        
        map.put(NormalExcelConstants.FILE_NAME, "orderList");
       
        PoibaseView.render(map, request, response, NormalExcelConstants.EASYPOI_EXCEL_VIEW);
    }
}

自定义处理

如果你想对导出字段进行一些自定义处理，EasyPoi也是支持的，比如在会员信息中，如果用户没有设置昵称，我们添加下暂未设置信息。

我们需要添加一个处理器继承默认的ExcelDataHandlerDefaultImpl类，然后在exportHandler方法中实现自定义处理逻辑；

public class MemberExcelDataHandler extends ExcelDataHandlerDefaultImpl {

  @Override
  public Object exportHandler(Member obj, String name, Object value) {
    if("昵称".equals(name)){
      String emptyValue = "暂未设置";
      if(value==null){
        return super.exportHandler(obj,name,emptyValue);
      }
      if(value instanceof String&&StrUtil.isBlank((String) value)){
        return super.exportHandler(obj,name,emptyValue);
      }
    }
    return super.exportHandler(obj, name, value);
  }

  @Override
  public Object importHandler(Member obj, String name, Object value) {
    return super.importHandler(obj, name, value);
  }
}

然后修改Controller中的接口，调用MemberExcelDataHandler处理器的setNeedHandlerFields设置需要自定义处理的字段，并调用ExportParams的setDataHandler设置自定义处理器；

**
 * EasyPoi导入导出测试Controller
 * Created by macro on 2021/10/12.
 */
@Controller
@Api(tags = "EasyPoiController", description = "EasyPoi导入导出测试")
@RequestMapping("/easyPoi")
public class EasyPoiController {

    @ApiOperation(value = "导出会员列表Excel")
    @RequestMapping(value = "/exportMemberList", method = RequestMethod.GET)
    public void exportMemberList(ModelMap map,
                                 HttpServletRequest request,
                                 HttpServletResponse response) {
        List memberList = LocalJsonUtil.getListFromJson("json/members.json", Member.class);
        ExportParams params = new ExportParams("会员列表", "会员列表", ExcelType.XSSF);
        //对导出结果进行自定义处理
        MemberExcelDataHandler handler = new MemberExcelDataHandler();
        handler.setNeedHandlerFields(new String[]{"昵称"});
        params.setDataHandler(handler);
        map.put(NormalExcelConstants.DATA_LIST, memberList);
        map.put(NormalExcelConstants.CLASS, Member.class);
        map.put(NormalExcelConstants.PARAMS, params);
        map.put(NormalExcelConstants.FILE_NAME, "memberList");
        PoibaseView.render(map, request, response, NormalExcelConstants.EASYPOI_EXCEL_VIEW);
    }
}