一 POM文件 版本更新快,可以自行搜jar依赖

图片说明

二 非必要依赖

Lombok:在生成模板类型可以使用,简便快捷,不用大量去写setter与getter和构造方法
常见Excel导入导出问题都存在类型转换类型,所以必备的三种常见类型转换

日期类

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/*
 * @author: GODV
 * @date: 2020/2/5 23:38
 * @params
 * @return:
 * @@Description: 日期辅助处理
 */
public class DateUtil {
    /*
     * @author: GODV
     * @date: 2020/2/5 23:38
     * @params
     * @return:
     * @@Description: 根据出生日期来计算年龄
     */
    public static int getAge(Date date) {
        if (date == null) {
            return 0;
        }
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        //2000
        int year = calendar.get(Calendar.YEAR);
        Calendar now = Calendar.getInstance();
        //2019
        int nowYear = now.get(Calendar.YEAR);
        return nowYear - year == 0 ? 1 : nowYear - year;
    }
    /*
     * @author: GODV
     * @date: 2020/2/5 23:39
     * @params
     * @return:
     * @@Description: String--->Date
     */
    public static Date getBirthday(String date) {
        if (date == null) {
            return null;
        }
        if (("").equals(date)){
            return null;
        }
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date birthday = null;
        try {
            birthday = format.parse(date);
        } catch (Exception e) {
            e.printStackTrace();
            birthday = null;
        }
        return birthday;
    }
    /*
     * @author: GODV
     * @date: 2020/2/5 23:39
     * @params
     * @return:
     * @@Description: Date--->String
     */
    public static String fomartBirthday(Date date) {
        if (date == null) {
            return "";
        }
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String birthday = format.format(date);
        return birthday;
    }
    /*
     * @author: GODV
     * @date: 2020/2/5 23:52
     * @params
     * @return:
     * @@Description: 获取时间
     */
    public static Date getLocalDate(){
        Date now =new Date();
        return now;
    }
    /*
     * @author: GODV
     * @date: 2020/2/16 18:50
     * @params 分钟化秒
     * @return:
     * @@Description: TODO(10分钟有效验证码)
     */
    public static String activeDate(Date date ,int time){
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        int s = time*60;
        Calendar calendar = Calendar.getInstance();
        calendar.clear();
        calendar.setTime(date);
        Calendar after = (Calendar) calendar.clone();
        after.add(Calendar.SECOND, s);
        String outAfter = format.format(after.getTime());
        return outAfter;
    }
}

只给日期类,通常还有很多类型的util,百度都是有现成的,看一下就是自己的了

三 核心部分 ExcelUtil.java

import com.alibaba.excel.EasyExcelFactory;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.context.AnalysisContext;
import com.alibaba.excel.event.AnalysisEventListener;
import com.alibaba.excel.metadata.BaseRowModel;
import com.alibaba.excel.metadata.Sheet;
import lombok.Data;
import lombok.Getter;
import lombok.Setter;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

@Slf4j
public class ExcelUtil {

    private static Sheet initSheet;

    static {
        initSheet = new Sheet(1, 0);
        initSheet.setSheetName("sheet");
        //设置自适应宽度
        initSheet.setAutoWidth(Boolean.TRUE);
    }

    /**
     * 读取少于1000行数据
     * @param filePath 文件绝对路径
     * @return
     */
    public static List<Object> readLessThan1000Row(String filePath){
        return readLessThan1000RowBySheet(filePath,null);
    }

    /**
     * 读小于1000行数据, 带样式
     * filePath 文件绝对路径
     * initSheet :
     *      sheetNo: sheet页码,默认为1
     *      headLineMun: 从第几行开始读取数据,默认为0, 表示从第一行开始读取
     *      clazz: 返回数据List<Object> 中Object的类名
     */
    public static List<Object> readLessThan1000RowBySheet(String filePath, Sheet sheet){
        if(!StringUtils.hasText(filePath)){
            return null;
        }

        sheet = sheet != null ? sheet : initSheet;

        InputStream fileStream = null;
        BufferedInputStream bufferedInputStream=null;
        try {
            fileStream = new FileInputStream(filePath);
            bufferedInputStream= new BufferedInputStream(fileStream);
            return EasyExcelFactory.read(bufferedInputStream, sheet);
        } catch (FileNotFoundException e) {
            log.info("找不到文件或文件路径错误, 文件:{}", filePath);
        }finally {
            try {
                if(fileStream != null){
                    fileStream.close();
                }
            } catch (IOException e) {
                log.info("excel文件读取失败, 失败原因:{}", e);
            }
        }
        return null;
    }

    /**
     * 读大于1000行数据
     * @param filePath 文件觉得路径
     * @return
     */
    public static List<Object> readMoreThan1000Row(String filePath){
        return readMoreThan1000RowBySheet(filePath,null);
    }

    /**
     * 读大于1000行数据, 带样式
     * @param filePath 文件觉得路径
     * @return
     */
    public static List<Object> readMoreThan1000RowBySheet(String filePath, Sheet sheet){
        if(!StringUtils.hasText(filePath)){
            return null;
        }

        sheet = sheet != null ? sheet : initSheet;

        InputStream fileStream = null;
        try {
            fileStream = new FileInputStream(filePath);
            ExcelListener excelListener = new ExcelListener();
            EasyExcelFactory.readBySax(fileStream, sheet, excelListener);
            return excelListener.getDatas();
        } catch (FileNotFoundException e) {
            log.error("找不到文件或文件路径错误, 文件:{}", filePath);
        }finally {
            try {
                if(fileStream != null){
                    fileStream.close();
                }
            } catch (IOException e) {
                log.error("excel文件读取失败, 失败原因:{}", e);
            }
        }
        return null;
    }

    /**
     * 生成excle
     * @param filePath  绝对路径, 如:/home/chenmingjian/Downloads/aaa.xlsx
     * @param data 数据源
     * @param head 表头
     */
    public static void writeBySimple(String filePath, List<List<Object>> data, List<String> head){
        writeSimpleBySheet(filePath,data,head,null);
    }

    /**
     * 生成excle
     * @param filePath 绝对路径, 如:/home/chenmingjian/Downloads/aaa.xlsx
     * @param data 数据源
     * @param sheet excle页面样式
     * @param head 表头
     */
    public static void writeSimpleBySheet(String filePath, List<List<Object>> data, List<String> head, Sheet sheet){
        sheet = (sheet != null) ? sheet : initSheet;

        if(head != null){
            List<List<String>> list = new ArrayList<>();
            head.forEach(h -> list.add(Collections.singletonList(h)));
            sheet.setHead(list);
        }

        OutputStream outputStream = null;
        ExcelWriter writer = null;
        try {
            outputStream = new FileOutputStream(filePath);
            writer = EasyExcelFactory.getWriter(outputStream);
            writer.write1(data,sheet);
        } catch (FileNotFoundException e) {
            log.error("找不到文件或文件路径错误, 文件:{}", filePath);
        }finally {
            try {
                if(writer != null){
                    writer.finish();
                }

                if(outputStream != null){
                    outputStream.close();
                }

            } catch (IOException e) {
                log.error("excel文件导出失败, 失败原因:{}", e);
            }
        }

    }

    /**
     * 生成excle
     * @param filePath 绝对路径, 如:/home/chenmingjian/Downloads/aaa.xlsx
     * @param data 数据源
     */
    public static void writeWithTemplate(String filePath, List<? extends BaseRowModel> data){
        writeWithTemplateAndSheet(filePath,data,null);
    }

    /**
     * 生成excle
     * @param filePath 绝对路径, 如:/home/chenmingjian/Downloads/aaa.xlsx
     * @param data 数据源
     * @param sheet excle页面样式
     */
    public static void writeWithTemplateAndSheet(String filePath, List<? extends BaseRowModel> data, Sheet sheet){
        if(CollectionUtils.isEmpty(data)){
            return;
        }

        sheet = (sheet != null) ? sheet : initSheet;
        sheet.setClazz(data.get(0).getClass());

        OutputStream outputStream = null;
        ExcelWriter writer = null;
        try {
            outputStream = new FileOutputStream(filePath);
            writer = EasyExcelFactory.getWriter(outputStream);
            writer.write(data,sheet);
        } catch (FileNotFoundException e) {
            log.error("找不到文件或文件路径错误, 文件:{}", filePath);
        }finally {
            try {
                if(writer != null){
                    writer.finish();
                }

                if(outputStream != null){
                    outputStream.close();
                }
            } catch (IOException e) {
                log.error("excel文件导出失败, 失败原因:{}", e);
            }
        }

    }

    /**
     * 生成多Sheet的excle
     * @param filePath 绝对路径, 如:/home/chenmingjian/Downloads/aaa.xlsx
     * @param multipleSheelPropetys
     */
    public static void writeWithMultipleSheel(String filePath,List<MultipleSheelPropety> multipleSheelPropetys){
        if(CollectionUtils.isEmpty(multipleSheelPropetys)){
            return;
        }

        OutputStream outputStream = null;
        ExcelWriter writer = null;
        try {
            outputStream = new FileOutputStream(filePath);
            writer = EasyExcelFactory.getWriter(outputStream);
            for (MultipleSheelPropety multipleSheelPropety : multipleSheelPropetys) {
                Sheet sheet = multipleSheelPropety.getSheet() != null ? multipleSheelPropety.getSheet() : initSheet;
                if(!CollectionUtils.isEmpty(multipleSheelPropety.getData())){
                    sheet.setClazz(multipleSheelPropety.getData().get(0).getClass());
                }
                writer.write(multipleSheelPropety.getData(), sheet);
            }

        } catch (FileNotFoundException e) {
            log.error("找不到文件或文件路径错误, 文件:{}", filePath);
        }finally {
            try {
                if(writer != null){
                    writer.finish();
                }

                if(outputStream != null){
                    outputStream.close();
                }
            } catch (IOException e) {
                log.error("excel文件导出失败, 失败原因:{}", e);
            }
        }

    }


    /*********************匿名内部类开始,可以提取出去******************************/

    @Data
    public static class MultipleSheelPropety{

        private List<? extends BaseRowModel> data;

        private Sheet sheet;
    }

    /**
     * 解析***,
     * 每解析一行会回调invoke()方法。
     * 整个excel解析结束会执行doAfterAllAnalysed()方法
     *
     * @author: chenmingjian
     * @date: 19-4-3 14:11
     */
    @Getter
    @Setter
    public static class ExcelListener extends AnalysisEventListener {

        private List<Object> datas = new ArrayList<>();

        /**
         * 逐行解析
         * object : 当前行的数据
         */
        @Override
        public void invoke(Object object, AnalysisContext context) {
            //当前行
            // context.getCurrentRowNum()
            if (object != null) {
                datas.add(object);
            }
        }


        /**
         * 解析完所有数据后会调用该方法
         */
        @Override
        public void doAfterAllAnalysed(AnalysisContext context) {
            //解析结束销毁不用的资源
        }

    }

    /************************匿名内部类结束,可以提取出去***************************/

}
  • 代码58行,我改成了BufferedInputStream,不改就会抛出异常,无法正常工作,也就说最好都改成BufferedInputStream。

  • 转载:https://blog.csdn.net/qq_32258777/article/details/89031479

  • 如果模仿上述链接使用@Test进行测试的,记得标准logback.xml路径和引入相应jar


四 中场休息

通过学习ExcelUtil.java的做法,他在读的时候分了1000行数据的概念,这里我也查阅了相关资料,存在是有必要的,其中的道理涉及内存释放的问题,我这种小白就不指手画脚了,大神们已经帮我们把接口写好了,直接用就行了。

五 导入Excel数据 通常都是伴随着持久化操作

导入都是毛毛雨,但是需要提示的是返回List<object>,你的pojo对象无法进行转换的的,可以采用反射的方式对数据进行转换
或者你感觉数据量不大的话,采用最老土的办法,Object对象去拿出来,再强制转换
这里需要注意的时候,既然是List<object>那就仔细看清楚了,或者来个遍历,因为Excel是有表头的,过了表头才是你需要的真正数据。</object></object>

六 导出Excel数据

模板制作

单sheet页无模型导出(最low的模型,也是最快最简单的)

//配置路径
String filePath = "‪C:\Users\Administrator\Desktop\applicantor.xlsx";
List<List<Object>> data = new ArrayList<>();
data.add(Arrays.asList("1","胡歌","男","18"));
data.add(Arrays.asList("2","彭于晏","男","18"));
data.add(Arrays.asList("3","霍建华","男","18"));
data.add(Arrays.asList("4","乔碧罗","女","18"));
List<String> head = Arrays.asList("序号", "姓名", "性别","年龄");
ExcelUtil.writeBySimple(filePath,data,head);

图片说明

单sheet页模型映射导出

import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.metadata.BaseRowModel;
import lombok.Data;
import lombok.EqualsAndHashCode;

@EqualsAndHashCode(callSuper = true)
@Data//这就是使用lombok的好处,主要是快捷
public class TableHeaderModel extends BaseRowModel {

    /**
     * value: 表头名称
     * index: 列的号, 0表示第一列
     */
    @ExcelProperty(value = "姓名", index = 0)
    private String name;

    @ExcelProperty(value = "年龄",index = 1)
    private int age;

    @ExcelProperty(value = "学校",index = 2)
    private String school;
}

String filePath = "C:\Users\Administrator\Desktop\applicantor.xlsx";
ArrayList<TableHeaderExcelProperty> data = new ArrayList<>();  
  TableHeaderModel tableHeaderExcelProperty = new TableHeaderExcelProperty();
  tableHeaderExcelProperty.setName("cmj" + i);
  tableHeaderExcelProperty.setAge(22 + i);
  tableHeaderExcelProperty.setSchool("清华大学" + i);
  data.add(tableHeaderExcelProperty);
  ExcelUtil.writeWithTemplate(filePath,data);

多sheet页模型导出

模型不变更换方法

 ArrayList<ExcelUtil.MultipleSheelPropety> list1 = new ArrayList<>();
 for(int j = 1; j < 4; j++){
      ArrayList<TableHeaderExcelProperty> list = new ArrayList<>();
      for(int i = 0; i < 4; i++){
          TableHeaderExcelProperty tableHeaderExcelProperty = new TableHeaderExcelProperty();
          tableHeaderExcelProperty.setName("cmj" + i);
          tableHeaderExcelProperty.setAge(22 + i);
          tableHeaderExcelProperty.setSchool("清华大学" + i);
          list.add(tableHeaderExcelProperty);
      }

      Sheet sheet = new Sheet(j, 0);
      sheet.setSheetName("sheet" + j);

      ExcelUtil.MultipleSheelPropety multipleSheelPropety = new ExcelUtil.MultipleSheelPropety();
      multipleSheelPropety.setData(list);
      multipleSheelPropety.setSheet(sheet);

      list1.add(multipleSheelPropety);

  }

  ExcelUtil.writeWithMultipleSheel("C:\Users\Administrator\Desktop\applicantor.xlsx",list1);
//这是直接用别人写的了

多表头模型导出


import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.metadata.BaseRowModel;
import lombok.Data;
import org.springframework.util.Assert;

import java.math.BigDecimal;


@Data
public class TaxVerificationOutEO extends BaseRowModel {
    @ExcelProperty(value = {"帐套编码","帐套编码"},index = 0)
    private String organizeId;

    @ExcelProperty(value = {"帐套名称","帐套名称"},index = 1)
    private String organizeName;

    @ExcelProperty(value = {"税款所属期","税款所属期"},index = 2)
    private String verificationDate;

    @ExcelProperty(value={ "上期留抵税额","申报值"},index = 3)
    private BigDecimal basisTax;
    @ExcelProperty(value = {"上期留抵税额","差异"},index = 4)
    private BigDecimal basisTaxDiff;

    @ExcelProperty(value = {"本期销项","申报值"},index = 5)
    private BigDecimal outputTax;
    @ExcelProperty(value = {"本期销项","差异"},index = 6)
    private BigDecimal outputTaxDiff;

    @ExcelProperty(value = {"本期进项","申报值"},index = 7)
    private BigDecimal inputTax;
    @ExcelProperty(value = {"本期进项","差异"},index = 8)
    private BigDecimal inputTaxDiff;


    @ExcelProperty(value = {"进项转出","申报值"},index = 9)
    private BigDecimal inputTransfer;
    @ExcelProperty(value ={"进项转出", "差异"},index = 10)
    private BigDecimal inputTransferDiff;


    @ExcelProperty(value = {"本期留抵税额","申报值"},index = 11)
    private BigDecimal taxResult;
    @ExcelProperty(value = {"本期留抵税额","差异"},index = 12)
    private BigDecimal taxResultDiff;
}

图片说明

七 总结

在阿里开发这款Excel导入导出,性能上可以说中上等,我用过POI,也用过JXL,相比之下,这款更适合自定义表格,一个pojo对象对应一个模板。
它最主要的强大地方就是可以根据自己的喜好去涉及模板属性,颜色,字体,背景色,读写高效。还可以插入图片,图片支持很多,Base64(二维码),URL都可以。
Java的反射可以去了解一下,方便我们可以看懂它的各种注解
下面链接详细解释了注解的作用:
https://blog.csdn.net/sinat_32366329/article/details/103109058

小白一枚,不喜勿喷