需求：现在需要完成通过post请求上传excel文件，并保存入库的功能

技术：SpringBoot + EasyExcel + postman 

 1.新增EasyExcel 依赖

<dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>easyexcel</artifactId>
      <version>2.1.6</version>
</dependency>

 2.新增excel数据对应的对象

package com.example.demo.model;

import com.alibaba.excel.annotation.ExcelProperty;
import lombok.Data;

/**
 * @author LWong
 * @date 2020/03/06
 */
@Data
public class ExportInfo {
    //@ExcelProperty注解可以使用value或者index进行匹配字段，不建议 index 和 name 同时用
    @ExcelProperty(value = "web-scraper-order", index = 0)
    private String order;

    @ExcelProperty(value = "web-scraper-start-url", index = 1)
    private String url;

    @ExcelProperty(value = "num", index = 2)
    private String num;

}

对应的excel数据是这样的，@ExcelProperty对应着表头信息

3. 新建监听器

package com.example.demo.util.excel;

import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.fastjson.JSON;
import com.google.common.collect.Lists;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.List;


/**
 * @author LWong
 * @date 2020/03/06
 */
public class ExcelListener extends AnalysisEventListener {

    private final static Logger LOGGER = LoggerFactory.getLogger(ExcelListener.class);

    private static final int BATCH_COUNT = 5;

     private List<Object> datas = Lists.newArrayList();

    @Override
    public void invoke(Object o, AnalysisContext analysisContext) {
        LOGGER.info("解析到一条数据:{}", JSON.toJSONString(o));
        //数据存储到list，
        datas.add(o);
        // 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 (datas.size() >= BATCH_COUNT) {
            saveData();
            // 存储完成清理 list
            datas.clear();
        }
    }

    @Override
    public void doAfterAllAnalysed(AnalysisContext analysisContext) {
        saveData();
        LOGGER.info("所有数据解析完成！");
    }

    /**
     * 入库
     */
    private void saveData() {
        LOGGER.info("{}条数据，开始存储数据库！", datas.size());
        //这个方法自己实现  能完成保存数据入库即可
        demoDAO.save(datas);
        LOGGER.info("存储数据库成功！");
    }

    public List<Object> getDatas() {
        return datas;
    }

    public void setDatas(List<Object> datas) {
        this.datas = datas;
    }
}

4.编写接口，即数据入口

package com.example.demo.controller;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelReader;
import com.alibaba.excel.read.metadata.ReadSheet;
import com.example.demo.model.ExportInfo;
import com.example.demo.util.excel.ExcelListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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;

import java.io.IOException;
import java.io.InputStream;

/**
 * @author LWong
 * @date 2020/03/06
 */
@RestController
@RequestMapping("excel")
public class ExcelController {

    private final static Logger logger = LoggerFactory.getLogger(ExcelController.class);

    @PostMapping("import")
    public void excelImport(@RequestParam(value = "file") MultipartFile serviceFile) throws IOException {
        ExcelReader excelReader = null;
        InputStream in = null;
        try {
            in = serviceFile.getInputStream();
            excelReader = EasyExcel.read(in, ExportInfo.class,
                    new ExcelListener()).build();
            ReadSheet readSheet = EasyExcel.readSheet(0).build();
            excelReader.read(readSheet);
        } catch (IOException ex) {
            logger.error("import excel to db fail", ex);
        } finally {
            in.close();
            // 这里一定别忘记关闭，读的时候会创建临时文件，到时磁盘会崩
            if (excelReader != null) {
                excelReader.finish();
            }
        }
    }
}

5.postman调试接口

postman上传文件教程：https://blog.csdn.net/maowendi/article/details/80537304

注意body的key是file  即@RequestParam指定的value

官网文档：

https://alibaba-easyexcel.github.io/