JAVA解析Excel工具easyexcel之快速上手

easyexcel的底层是poi，它是对poi的封装，原理是在读取excel文件达到一定的数量后进行清空内存，并再继续读取内容，从而达到防止内存溢出的问题。
64M内存1分钟内读取75M(46W行25列)的Excel：

简单上手三步骤：
1、编写监听器，当读取数据达到一定数量时进行操作，并清空内存空间

package com.alibaba.easyexcel.test.temp.read;

import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.excel.metadata.CellData;
import com.alibaba.fastjson.JSON;

/**
 * 模板的读取类
 *
 * @author
 */
public class HDListener extends AnalysisEventListener {
    private static final Logger LOGGER = LoggerFactory.getLogger(HDListener.class);
    /**
     * 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;

    @Override
    public void invokeHeadMap(Map headMap, AnalysisContext context) {
        LOGGER.info("HEAD:{}", JSON.toJSONString(headMap));
        LOGGER.info("total:{}", context.readSheetHolder().getTotal());

    }

    @Override
    public void invoke(HeadReadData data, AnalysisContext context) {
        LOGGER.info("index:{}", context.readRowHolder().getRowIndex());
        LOGGER.info("解析到一条数据:{}", JSON.toJSONString(data));
    }

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

}

2、编写读取excel文件的对象，会根据该对象进行数据封装返回

package com.alibaba.easyexcel.test.temp.read;

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

/**
 * 临时测试
 *
 * @author
 **/
@Data
@Accessors(chain = true)
public class HeadReadData {
    @ExcelProperty("头1")
    private String h1;
    @ExcelProperty({"头", "头2"})
    private String h2;
}

3、创建easyexcel读取对象读取文件内容

package com.alibaba.easyexcel.test.temp.read;

import java.io.File;

import org.junit.Ignore;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.cache.Ehcache;

/**
 * 临时测试
 *
 * @author
 **/
@Ignore
public class HeadReadTest {
    private static final Logger LOGGER = LoggerFactory.getLogger(HeadReadTest.class);

    @Test
    public void test() throws Exception {
        File file = new File("D:\\test\\headt1.xls");
        EasyExcel.read(file, HeadReadData.class, new HDListener()).sheet(0).doRead();

    }
}