SpringBoot整合EasyExcel实现导入导出数据

前言

创建一个普通的maven项目即可

项目目录结构

1.前端

存放在resources/static 下

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <!-- 开发环境版本，包含了有帮助的命令行警告 -->
    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>
    <!-- 引入样式 -->
    <link
      rel="stylesheet"
      href="https://unpkg.com/element-ui/lib/theme-chalk/index.css" rel="external nofollow" 
    />
    <!-- 引入组件库 -->
    <script src="https://unpkg.com/element-ui/lib/index.js"></script>
    <script src="https://unpkg.com/axios/dist/axios.min.js"></script>
  </head>
  <body>
    <div id="app">
      <div class="app-container">
        <div style="margin-bottom: 10px">
          <el-button
            @click="dialogVisible = true"
            type="primary"
            size="mini"
            icon="el-icon-download"
          >
            导入Excel
          </el-button>
          <el-dialog
            title="数据字典导入"
            :visible.sync="dialogVisible"
            width="30%"
          >
            <el-form>
              <el-form-item label="请选择Excel文件">
                <el-upload
                  :auto-upload="true"
                  :multiple="false"
                  :limit="1"
                  :on-exceed="fileUploadExceed"
                  :on-success="fileUploadSuccess"
                  :on-error="fileUploadError"
                  :action="importUrl"
                  name="file"
                  accept="application/vnd.ms-excel,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
                >
                  <!--accept 只接受某种格式的文件-->
                  <el-button size="small" type="primary">点击上传</el-button>
                </el-upload>
              </el-form-item>
            </el-form>
            <div slot="footer" class="dialog-footer">
              <el-button @click="dialogVisible = false">取消</el-button>
            </div>
          </el-dialog>

          <!-- 导出 -->
          <el-button
            @click="exportData"
            type="primary"
            size="mini"
            icon="el-icon-upload2"
          >
            导出Excel
          </el-button>

          <!-- 数据展示 -->
          <el-table :data="list" stripe style="width: 100%">
            <el-table-column prop="name" label="姓名" width="180">
            </el-table-column>
            <el-table-column prop="birthday" label="生日" width="180">
            </el-table-column>
            <el-table-column prop="salary" label="薪资"> </el-table-column>
          </el-table>
          <div>
            <el-pagination
              @size-change="handleSizeChange"
              @current-change="handleCurrentChange"
              :current-page="pageNum"
              :page-sizes="[2, 5, 10,  20]"
              :page-size="pageSize"
              background
              layout="total, sizes, prev, pager, next, jumper"
              :total="total"
            >
            </el-pagination>
          </div>
        </div>
      </div>
    </div>
  </body>
  <script>
    new Vue({
      el: '#app',
      data() {
        return {
          dialogVisible: false, //文件上传对话框是否显示
          list: [], // 字典的数据
          importUrl: 'http://localhost:8811/api/excel/import',
          pageNum: 1, // 页数
          pageSize: 5, // 每页条数
          total: 1000,
        }
      },
      created() {
        this.showList()
      },
      methods: {
        showList() {
          //使用自定义配置
          const request = axios.create({
            baseURL: 'http://localhost:8811', //url前缀
            timeout: 1000, //超时时间
            // headers: { token: 'helen123456' }, //携带令牌
          })
          request
            .get('/api/excel/list', {
              params: {
                pageNum: this.pageNum,
                pageSize: this.pageSize,
              },
            })
            .then((res) => {
              this.total = res.data.size
              this.list = res.data.list
              console.log(res)
            })
        },
        // 上传多于一个文件时
        fileUploadExceed() {
          this.$message.warning('只能选取一个文件')
        },
		// 导出
        exportData() {
          window.location.href = 'http://localhost:8811/api/excel/export'
        },

        //上传成功回调
        fileUploadSuccess(response) {
          if (response.code === 0) {
            this.$message.success('数据导入成功')
            this.dialogVisible = false
          } else {
            this.$message.error(response.message)
          }
        },

        //上传失败回调
        fileUploadError(error) {
          this.$message.error('数据导入失败')
        },
        /**
         * 用户所选择当前页面展示的数据条数
         */
        handleSizeChange(val) {
          console.log(`每页 ${val} 条`)
          this.pageSize = val
          this.showList()
        },
        handleCurrentChange(val) {
          console.log(`当前页: ${val}`)
          this.pageNum = val
          this.showList()
        },
      },
    })
  </script>
</html>

2.数据库

CREATE TABLE `student` (
  `name` varchar(255) DEFAULT NULL COMMENT '姓名',
  `birthday` datetime DEFAULT NULL COMMENT '生日',
  `salary` decimal(10,4) DEFAULT NULL COMMENT '薪资'
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

3.后端

3.1 contrller

StudentController

@Slf4j
@RestController
@CrossOrigin
@RequestMapping("/api/excel/")
public class StudentController {

    @Resource
    private StudentMapper studentMapper;

    @GetMapping("list")
    public HashMap<String, Object> list(@RequestParam int pageNum,@RequestParam int pageSize){
        // 分页查询
        Page<Student> page = new Page<>(pageNum, pageSize);
        studentMapper.selectPage(page,null);
        
        // 封装数据
        HashMap<String, Object> map = new HashMap<>();
        ArrayList<ExcelStudentDTO> excelDictDTOList = new ArrayList<>();
        // 转换数据
        page.getRecords().forEach(student -> {
            ExcelStudentDTO studentDTO = new ExcelStudentDTO();
            BeanUtils.copyProperties(student,studentDTO);
            excelDictDTOList.add(studentDTO);
        });
        
        map.put("list",excelDictDTOList);
        map.put("size",page.getTotal());
        return map;
    }

    /**
     * 导入
     * @param file 文件对象
     */
    @RequestMapping("import")
    @Transactional(rollbackFor = {Exception.class})
    public String importData( @RequestParam("file") MultipartFile file){
        try {
            // 读取文件流
            EasyExcel.read
                    (file.getInputStream(),// 前端上传的文件
                            ExcelStudentDTO.class,// 跟excel对应的实体类
                            new ExcelDictDTOListener(studentMapper))// 监听器 
                    .excelType(ExcelTypeEnum.XLSX)// excel的类型
                    .sheet("模板").doRead();
            log.info("importData finished");
        } catch (IOException e) {
           log.info("失败");
           e.printStackTrace();
        }
        return "上传成功";
    }

    /**
     * 导入
     */
    @GetMapping("export")
    public String exportData(HttpServletResponse response){

        try {
            // 设置响应体内容
            response.setContentType("application/vnd.ms-excel");
            response.setCharacterEncoding("utf-8");

            // 这里URLEncoder.encode可以防止中文乱码 当然和easyexcel没有关系
            String fileName = URLEncoder.encode("myStu", "UTF-8").replaceAll("\\+", "%20");
            response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx");
            EasyExcel.write(response.getOutputStream()
                    ,ExcelStudentDTO.class).sheet().doWrite(studentMapper.selectList(null));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "上传成功";
    }

}

3.2 mapper

StudentMapper

@Mapper
public interface StudentMapper extends BaseMapper<Student> {
    void insertBatch(List<ExcelStudentDTO> list);
}

StudentMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="look.word.mapper.StudentMapper">
  <insert id="insertBatch" >
    insert into student(name, birthday, salary)
    values
    <foreach collection="list"   item="item" separator=",">
               (
        #{item.name} ,
        #{item.birthday} ,
        #{item.salary} 
        )
    </foreach>
  </insert>
</mapper>

3.3 bean

ExcelStudentDTO

导入数据时要保证excel中列名和ExcelStudentDTO一致奥

/**
 * excel对应的实体类
 * @author jiejie
 */
@Data
public class ExcelStudentDTO {
	// excel中的列名
    @ExcelProperty("姓名")
    private String name;

    @ExcelProperty("生日")
    private Date birthday;

    @ExcelProperty("薪资")
    private BigDecimal salary;
}

Student

/**
 * 数据库对应的实体类
 * @author jiejie
 */
@Data
@TableName(value = "student")
public class Student {
    /**
     * 姓名
     */
    @TableField(value = "name")
    private String name;

    /**
     * 生日
     */
    @TableField(value = "birthday")
    private Date birthday;

    /**
     * 薪资
     */
    @TableField(value = "salary")
    private BigDecimal salary;

    public static final String COL_NAME = "name";

    public static final String COL_BIRTHDAY = "birthday";

    public static final String COL_SALARY = "salary";
}

3.4 listener

官方文档

EasyExcel读取文件需要用到

ExcelDictDTOListener

/**
 * 监听
 * 再读取数据的同时 对数据进行插入操作
 * @author : look-word
 * @date : 2022-05-10 21:35
 **/
@Slf4j
//@AllArgsConstructor //全参
@NoArgsConstructor //无参
public class ExcelDictDTOListener extends AnalysisEventListener<ExcelStudentDTO> {


    /**
     * 每隔5条存储数据库，实际使用中可以3000条，然后清理list ，方便内存回收
     */
    private static final int BATCH_COUNT = 5;
    List<ExcelStudentDTO> list = new ArrayList<ExcelStudentDTO>();

    private StudentMapper studentMapper;

    //传入mapper对象
    public ExcelDictDTOListener(StudentMapper studentMapper) {
        this.studentMapper = studentMapper;
    }

    /**
     *遍历每一行的记录
     * @param data
     * @param context
     */
    @Override
    public void invoke(ExcelStudentDTO data, AnalysisContext context) {
        log.info("解析到一条记录: {}", data);
        list.add(data);
        // 达到BATCH_COUNT了，需要去存储一次数据库，防止数据几万条数据在内存，容易OOM
        if (list.size() >= BATCH_COUNT) {
            saveData();
            // 存储完成清理 list
            list.clear();
        }
    }

    /**
     * 所有数据解析完成了 都会来调用
     */
    @Override
    public void doAfterAllAnalysed(AnalysisContext context) {
        // 这里也要保存数据，确保最后遗留的数据也存储到数据库
        saveData();
        log.info("所有数据解析完成！");
    }

    /**
     * 加上存储数据库
     */
    private void saveData() {
        log.info("{}条数据，开始存储数据库！", list.size());
        studentMapper.insertBatch(list);  //批量插入
        log.info("存储数据库成功！");
    }
}

3.5 config

mybatisPlus分页插件

MybatisPlusConfig

@Configuration
public class MybatisPlusConfig {

    /**
     * 新的分页插件,一缓和二缓遵循mybatis的规则,
     * 需要设置 MybatisConfiguration#useDeprecatedExecutor = false
     * 避免缓存出现问题(该属性会在旧插件移除后一同移除)
     */
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        PaginationInnerInterceptor paginationInnerInterceptor = new PaginationInnerInterceptor();
        paginationInnerInterceptor.setDbType(DbType.MYSQL);
        paginationInnerInterceptor.setOverflow(true);
        interceptor.addInnerInterceptor(paginationInnerInterceptor);
        return interceptor;
    }

    @Bean
    public ConfigurationCustomizer configurationCustomizer() {
        return configuration -> configuration.setUseDeprecatedExecutor(false);
    }
}

3.6 配置文件

application.yaml

server:
  port: 8811
spring:
  datasource: # mysql数据库连接
    type: com.zaxxer.hikari.HikariDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/2022_source_springboot?serverTimezone=GMT%2B8&characterEncoding=utf-8
    username: root
    password: 317311
mybatis-plus:
  configuration:# sql日志
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
  mapper-locations:
    - classpath:mapper/*.xml

4.启动测试

启动springboot哦

页面效果图

导出效果

注意