springboot集成easyPoi实现excel数据导入到Mysql数据库

easyPoi官方文档：http://easypoi.mydoc.io/
通过Mybatis generator生成相关Tbxxx，TbxxxExample，TbxxxMapper.java，TbxxxMapper.xml，TbxxxService

引入依赖：

		<dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-base</artifactId>
            <version>3.2.0</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-web</artifactId>
            <version>3.2.0</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-annotation</artifactId>
            <version>3.2.0</version>
        </dependency>

注解实体类：
```
import cn.afterturn.easypoi.excel.annotation.Excel;
import com.yun.cloud.base.model.BaseModel;
import lombok.Data;

import java.io.Serializable;

@Data
public class TbProductStandard extends BaseModel implements Serializable {
    private String id;

    @Excel(name = "code")
    private String code;

    @Excel(name = "parent_code")
    private String parentId;

    @Excel(name = "type_name")
    private String typeName;
}
```
相关注解介绍：

@Excel 作用到实体类字段上面,是对Excel一列的一个描述

@ExcelCollection 表示一个集合,主要针对一对多的导出,比如一个老师对应多个科目,科目就可以用集合表示

@ExcelEntity 表示一个继续深入导出的实体,但他没有太多的实际意义,只是告诉系统这个对象里面同样有导出的字段

@ExcelIgnore 和名字一样表示这个字段被忽略跳过这个导导出

@ExcelTarget 这个是作用于最外层的对象,描述这个对象的id,以便支持一个对象可以针对不同导出做出不同处理
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原文链接：https://blog.csdn.net/weixin_41922289/article/details/100191112
- 受注解的excel格式：

设置excel导入导出工具类：

import cn.afterturn.easypoi.excel.ExcelExportUtil;
import cn.afterturn.easypoi.excel.ExcelImportUtil;
import cn.afterturn.easypoi.excel.entity.ExportParams;
import cn.afterturn.easypoi.excel.entity.ImportParams;
import cn.afterturn.easypoi.excel.entity.enmus.ExcelType;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;

public class ProductExcelUtils {
    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName,
                                   boolean isCreateHeader, HttpServletResponse response) {
        ExportParams exportParams = new ExportParams(title, sheetName);
        exportParams.setCreateHeadRows(isCreateHeader);
        defaultExport(list, pojoClass, fileName, response, exportParams);
    }

    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName,
                                   HttpServletResponse response) {
        defaultExport(list, pojoClass, fileName, response, new ExportParams(title, sheetName));
    }

    public static void exportExcel(List<Map<String, Object>> list, String fileName, HttpServletResponse response) {
        defaultExport(list, fileName, response);
    }

    private static void defaultExport(List<?> list, Class<?> pojoClass, String fileName, HttpServletResponse response,
                                      ExportParams exportParams) {
        Workbook workbook = ExcelExportUtil.exportExcel(exportParams, pojoClass, list);
        if (workbook != null)
            ;
        downLoadExcel(fileName, response, workbook);
    }

    private static void downLoadExcel(String fileName, HttpServletResponse response, Workbook workbook) {
        try {
            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            // throw new NormalException(e.getMessage());
        }
    }

    private static void defaultExport(List<Map<String, Object>> list, String fileName, HttpServletResponse response) {
        Workbook workbook = ExcelExportUtil.exportExcel(list, ExcelType.HSSF);
        if (workbook != null)
            ;
        downLoadExcel(fileName, response, workbook);
    }

    public static <T> List<T> importExcel(String filePath, Integer titleRows, Integer headerRows, Class<T> pojoClass) {
        if (StringUtils.isBlank(filePath)) {
            return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list = null;
        try {
            list = ExcelImportUtil.importExcel(new File(filePath), pojoClass, params);
        } catch (NoSuchElementException e) {
            // throw new NormalException("模板不能为空");
        } catch (Exception e) {
            e.printStackTrace();
            // throw new NormalException(e.getMessage());
        }
        return list;
    }

    public static <T> List<T> importExcel(MultipartFile file, Integer titleRows, Integer headerRows,
                                          Class<T> pojoClass) {
        if (file == null) {
            return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list = null;
        try {
            list = ExcelImportUtil.importExcel(file.getInputStream(), pojoClass, params);
        } catch (NoSuchElementException e) {
            // throw new NormalException("excel文件不能为空");
        } catch (Exception e) {
            // throw new NormalException(e.getMessage());
            System.out.println(e.getMessage());
        }
        return list;
    }
}

controller层:

import com.yun.cloud.base.result.Result;
import com.yun.cloud.gap.business.ProductStandardBusiness;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

@RestController
@RequestMapping("/productstandard")
public class ProductStandardController {
    @Autowired
    private ProductStandardBusiness productStandardBusiness;
    /**
     * 导入excel
     * @param file
     * @return
     */
    @PostMapping("/importExcel")
    public Result importExcel(@RequestParam("file") MultipartFile file) {
        return productStandardBusiness.importExcel(file);
    }
}

business层：

import cn.afterturn.easypoi.excel.ExcelImportUtil;
import cn.afterturn.easypoi.excel.entity.ImportParams;
import cn.afterturn.easypoi.excel.entity.result.ExcelImportResult;
import com.alibaba.fastjson.JSONObject;
import com.yun.cloud.base.result.Result;
import com.yun.cloud.base.utils.IdGenUtil;
import com.yun.cloud.gap.model.TbProductStandard;
import com.yun.cloud.gap.model.TbProductStandardExample;
import com.yun.cloud.gap.service.TbProductStandardService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.util.List;

@Slf4j
@Service("ProductStandardBusiness")
public class ProductStandardBusiness {
    @Autowired
    private TbProductStandardService tbProductStandardService;

    @Value("${machine}")
    private int machineId;

    @Value("${datacenter}")
    private int dataCenterId;

    public Result importExcel(MultipartFile file) {
        ImportParams importParams = new ImportParams();
        // 数据处理
        importParams.setHeadRows(1);
        importParams.setTitleRows(1);
        // 需要验证
        importParams.setNeedVerfiy(false);
        try {
            ExcelImportResult<TbProductStandard> result = ExcelImportUtil.importExcelMore(file.getInputStream(), TbProductStandard.class,
                    importParams);
            List<TbProductStandard> tbProductStandardList = result.getList();
            for (TbProductStandard tbProductStandard : tbProductStandardList) {
                log.info("从Excel导入数据到数据库的详细为 ：{}", JSONObject.toJSONString(tbProductStandard));
                //保存到mysql
                String id = IdGenUtil.getNextId(machineId,dataCenterId);
                tbProductStandard.setId(id);
                int i = tbProductStandardService.insertSelective(tbProductStandard);
                if(i < 1){
                    log.error("保存失败");
                    return Result.err("保存失败");
                }
            }
            log.info("从Excel导入数据一共 {} 行 ", tbProductStandardList.size());
        } catch (Exception e) {
            log.error("导入失败：{}", e.getMessage());
            return Result.err("导入失败");
        }
        return Result.suc();
    }
}