POI和easyExcel操作

POI

在这里插入图片描述

easyExcel

POI和easyExcel操作_第1张图片

POI和easyExcel对比

POI和easyExcel操作_第2张图片

POI-Excel 写

版本差别

xls-03版 一共有65536行,xlsx-07版 则没有限制。

项目包结构

POI和easyExcel操作_第3张图片

工作簿

03版本 HSSFWorkbook,07版本 XSSFWorkbook

代码

pom.xml


<dependencies>
    
    <dependency>
        <groupId>org.apache.poigroupId>
        <artifactId>poiartifactId>
        <version>3.9version>
    dependency>
    
    <dependency>
        <groupId>org.apache.poigroupId>
        <artifactId>poi-ooxmlartifactId>
        <version>3.9version>
    dependency>
    
    <dependency>
        <groupId>joda-timegroupId>
        <artifactId>joda-timeartifactId>
        <version>2.10.1version>
    dependency>
    
    <dependency>
        <groupId>junitgroupId>
        <artifactId> junitartifactId>
        <version>4.12version>
    dependency>
dependencies>

ExcelWriteTest.java

package com.lm;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.joda.time.DateTime;
import org.junit.Test;

import java.io.FileOutputStream;

public class ExcelWriteTest {

    //存储路径
    String PATH = "C:/Users/Lenovo/Desktop/POI/";

    @Test
    public void testExcel03() throws Exception {
        //1.创建工作簿
        Workbook workbook = new HSSFWorkbook();
        //2.创建工作表
        Sheet sheet = workbook.createSheet("工作表一");
        //3.创建行
        Row row_1 = sheet.createRow(0); //第一行
        //4.创建单元格
        Cell cell_11 = row_1.createCell(0); //(1,1)
        cell_11.setCellValue("姓名"); // 输入数据

        Cell cell_12 = row_1.createCell(1); //(1,2)
        cell_12.setCellValue("性别");

        Cell cell_13 = row_1.createCell(2); //(1,3)
        cell_13.setCellValue("填表日期");

        Row row_2 = sheet.createRow(1); //第二行
        Cell cell_21 = row_2.createCell(0); //(2,1)
        cell_21.setCellValue("李白");

        Cell cell_22 = row_2.createCell(1); //(2,2)
        cell_22.setCellValue("男");

        Cell cell_23 = row_2.createCell(2); //(2,3)
        String time = new DateTime().toString("yyyy-MM-dd HH:mm:ss");
        cell_23.setCellValue(time);

        //生成一张excel表(IO 流)03版本.xls
        FileOutputStream fileOutputStream = new FileOutputStream(PATH + "Excel03.xls");
        workbook.write(fileOutputStream); //输出
        fileOutputStream.close(); //关闭流
        System.out.println("excel03生成成功!");
    }

    @Test
    public void testExcel07() throws Exception {
        //1.创建工作簿
        Workbook workbook = new XSSFWorkbook();
        //2.创建工作表
        Sheet sheet = workbook.createSheet("工作表一");
        //3.创建行
        Row row_1 = sheet.createRow(0); //第一行
        //4.创建单元格
        Cell cell_11 = row_1.createCell(0); //(1,1)
        cell_11.setCellValue("姓名"); // 输入数据

        Cell cell_12 = row_1.createCell(1); //(1,2)
        cell_12.setCellValue("性别");

        Cell cell_13 = row_1.createCell(2); //(1,3)
        cell_13.setCellValue("填表日期");

        Row row_2 = sheet.createRow(1); //第二行
        Cell cell_21 = row_2.createCell(0); //(2,1)
        cell_21.setCellValue("李白");

        Cell cell_22 = row_2.createCell(1); //(2,2)
        cell_22.setCellValue("男");

        Cell cell_23 = row_2.createCell(2); //(2,3)
        String time = new DateTime().toString("yyyy-MM-dd HH:mm:ss");
        cell_23.setCellValue(time);

        //生成一张excel表(IO 流)07版本.xlsx
        FileOutputStream fileOutputStream = new FileOutputStream(PATH + "Excel07.xlsx");
        workbook.write(fileOutputStream); //输出
        fileOutputStream.close(); //关闭流
        System.out.println("excel07生成成功!");
    }
}

数据批量导入

大文件写 HSSF 03版本

缺点:最多只能处理65536行,否则回抛异常

java.lang.IllegalArgumentException: Invalid row number (65536) outside allowable range (0..65535)

优点:过程中写入缓存,不操作磁盘,最后一次性写入磁盘,速度快

ExcelWriteTest.java

   @Test
    public void testWrite03BigData() throws Exception {
        //时间
        long begin = System.currentTimeMillis();

        //创建簿
        Workbook workbook = new HSSFWorkbook();
        //创建表
        Sheet sheet = workbook.createSheet();
        //写入数据
        for (int rowNum = 0; rowNum < 65536; rowNum++){
            Row row = sheet.createRow(rowNum);
            for (int cellNum = 0; cellNum <10; cellNum++){
                Cell cell = row.createCell(cellNum);
                cell.setCellValue(cellNum);
            }
        }
        System.out.println("write over");
        //输出流
        FileOutputStream fileOutputStream = new FileOutputStream( PATH + "testBigData03.xls");
        workbook.write(fileOutputStream);
		fileOutputStream.close(); //关闭流
        long end = System.currentTimeMillis();
        System.out.println((double)(end-begin)/1000);

    }

大文件写XSSF

缺点:写数据时速度非常慢,非常耗内存,会发生内存溢出,如100万条数据时

优点:可以写较大的数据,如20万条数据

ExcelWriteTest.java

@Test
    public void testWrite07BigData() throws Exception {
        //时间
        long begin = System.currentTimeMillis();

        //创建簿
        Workbook workbook = new XSSFWorkbook();
        //创建表
        Sheet sheet = workbook.createSheet();
        //写入数据
        for (int rowNum = 0; rowNum < 65537; rowNum++){
            Row row = sheet.createRow(rowNum);
            for (int cellNum = 0; cellNum <10; cellNum++){
                Cell cell = row.createCell(cellNum);
                cell.setCellValue(cellNum);
            }
        }
        System.out.println("write over");
        //输出流
        FileOutputStream fileOutputStream = new FileOutputStream( PATH + "testBigData07.xlsx");
        workbook.write(fileOutputStream);
		fileOutputStream.close(); //关闭流
        long end = System.currentTimeMillis();
        System.out.println((double)(end-begin)/1000);

    }

大文件写SXSSF

优点:可以写非常大的数据量,如100万条甚至更多,写数据速度快,占用内存更少

注意

过程会产生临时文件,需要清理临时文件

默认为100条记录被保存在内存中,如果超过超过这个数量,则最前面的数据写入临时文件

如果想自定义内存中的数量,可以使用new SXSSFWorkbook(数量)

ExcelWriteTest.java

    @Test
    public void testSupperWrite07BigData() throws Exception {
        //时间
        long begin = System.currentTimeMillis();

        //创建簿
        Workbook workbook = new SXSSFWorkbook();
        //创建表
        Sheet sheet = workbook.createSheet();
        //写入数据
        for (int rowNum = 0; rowNum < 100000; rowNum++){
            Row row = sheet.createRow(rowNum);
            for (int cellNum = 0; cellNum <10; cellNum++){
                Cell cell = row.createCell(cellNum);
                cell.setCellValue(cellNum);
            }
        }
        System.out.println("write over");
        //输出流
        FileOutputStream fileOutputStream = new FileOutputStream( PATH + "testSuperData07.xlsx");
        workbook.write(fileOutputStream);//写入
        fileOutputStream.close(); //关闭流
        ((SXSSFWorkbook) workbook).dispose();//清除临时文件
        long end = System.currentTimeMillis();
        System.out.println((double)(end-begin)/1000);

    }

POI-Excel 读

03版本

ExcelReadTest.java

package com.lm;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.junit.Test;

import java.io.FileInputStream;

public class ExcelReadTest {

    //存储路径
    String PATH = "C:/Users/Lenovo/Desktop/POI/";

    @Test
    public void testRead03() throws Exception {
        //获取文件流
        FileInputStream inputStream = new FileInputStream( PATH + "Excel03.xls" );

        //1.获取工作簿,Excel里面的功能都能使用
        Workbook workbook = new HSSFWorkbook(inputStream);
        //2.获得表,通过下标获取
        Sheet sheet = workbook.getSheetAt(0);
        //3.获得行
        Row row = sheet.getRow(0);
        //4.获得列
        Cell cell = row.getCell(0);

        //getStringCellValue获取字符串类型的内容
        System.out.println(cell.getStringCellValue());
        //getNumericCellValue获取数字类型的内容
       // System.out.println(cell.getNumericCellValue());
        inputStream.close();
    }
}

07版本

ExcelReadTest.java

 @Test
    public void testRead07() throws Exception {
        //获取文件流
        FileInputStream inputStream = new FileInputStream( PATH + "Excel07.xlsx" );

        //1.获取工作簿,Excel里面的功能都能使用
        Workbook workbook = new XSSFWorkbook(inputStream);
        //2.获得表,通过下标获取
        Sheet sheet = workbook.getSheetAt(0);
        //3.获得行
        Row row = sheet.getRow(0);
        //4.获得列
        Cell cell = row.getCell(0);

        //getStringCellValue获取字符串类型的内容
        System.out.println(cell.getStringCellValue());
        //getNumericCellValue获取数字类型的内容
        // System.out.println(cell.getNumericCellValue());
        inputStream.close();
    }

:获取值的类型需要注意

读取不同数据类型 (重要)

ExcelReadTest.java

    @Test
    public void testCellType() throws Exception {
        //获取文件流
        FileInputStream inputStream = new FileInputStream( PATH + "明细表.xlsx" );

        //创建工作簿
        Workbook workbook = new XSSFWorkbook(inputStream);
        Sheet sheet = workbook.getSheetAt(0);
        //获取标题内容
        Row rowTitle = sheet.getRow(0);
        if (rowTitle != null){
            int cellCount = rowTitle.getPhysicalNumberOfCells();
            for (int cellNum = 0; cellNum < cellCount; cellNum++ ){
                Cell cell = rowTitle.getCell(cellNum);
                if (cell != null){
                    int cellType = cell.getCellType();
                    String cellValue = cell.getStringCellValue();
                    System.out.print(cellValue + " | ");
                }
            }
            System.out.println();
        }

        //获取表中的内容
        int rowCount = sheet.getPhysicalNumberOfRows();
        for (int rowNum = 1; rowNum < rowCount; rowNum++) {
            Row rowData = sheet.getRow(rowNum);
            if (rowData != null) {
                //读取列
                int cellCount = rowTitle.getPhysicalNumberOfCells();
                for (int cellNum = 0; cellNum < cellCount; cellNum++) {
                    System.out.print("[" + (rowNum + 1) + "-" + (cellNum + 1) + "]");

                    Cell cell = rowData.getCell(cellNum);
                    //匹配列的数据类型
                    if (cell != null) {
                        int cellType = cell.getCellType();
                        String cellValue = "";
       
                        switch (cellType) {
                            case HSSFCell.CELL_TYPE_STRING: //String
                                System.out.print("[String]");
                                cellValue = cell.getStringCellValue();
                                break;
                            case HSSFCell.CELL_TYPE_BOOLEAN: //Boolean
                                System.out.print("[Boolean]");
                                cellValue = String.valueOf(cell.getBooleanCellValue());
                                break;
                            case HSSFCell.CELL_TYPE_BLANK: //空
                                System.out.print("[Blank]");
                                break;
                            case HSSFCell.CELL_TYPE_NUMERIC: //数字(日期、普通数字)
                                System.out.print("[Numeric]");
                                if (HSSFDateUtil.isCellDateFormatted(cell)) { //日期
                                    System.out.print("[日期]");
                                    Date date = cell.getDateCellValue();
                                    cellValue = new DateTime(date).toString("yyyy-MM-dd");
                                }else{
                                    //不是日期格式,防止数字过长
                                    System.out.print("[转换为String输出]");
                                    cell.setCellType(HSSFCell.CELL_TYPE_STRING);
                                    cellValue = cell.toString();
                                }
                                break;
                            case HSSFCell.CELL_TYPE_ERROR: //Error
                                System.out.print("[数据类型错误]");
                                break;
                        }
                        System.out.println(cellValue);
                    }
                }
            }
        }
        inputStream.close();
    }

计算公式(了解)

ExcelReadTest.java

 @Test
    public void testFormula() throws Exception {
        FileInputStream inputStream = new FileInputStream( PATH + "公式.xlsx" );
        Workbook workbook = new XSSFWorkbook(inputStream);
        Sheet sheet = workbook.getSheetAt(0);

        Row row = sheet.getRow(4);
        Cell cell = row.getCell(0);

        //获取计算公式
        FormulaEvaluator formulaEvaluator = new XSSFFormulaEvaluator((XSSFWorkbook)workbook);

        //输出单元格的内容
        int cellType = cell.getCellType();
        switch (cellType){
            case Cell.CELL_TYPE_FORMULA: //公式
                String formula = cell.getCellFormula();
                System.out.println(formula);
                //计算
                CellValue evaluate = formulaEvaluator.evaluate(cell);
                String cellValue = evaluate.formatAsString();
                System.out.println(cellValue);
                
                break;
        }
    }

公式.xlsx

POI和easyExcel操作_第4张图片

EasyExcel操作

参考文档 https://www.yuque.com/easyexcel/doc/easyexcel

pom.xml

        
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>easyexcelartifactId>
            <version>2.2.6version>
        dependency>
		
        <dependency>
            <groupId>org.projectlombokgroupId>
            <artifactId>lombokartifactId>
            <version>1.18.12version>
        dependency>
        
        <dependency>
            <groupId>com.alibabagroupId>
            <artifactId>fastjsonartifactId>
            <version>1.2.62version>
        dependency>

:导入easyexcel依赖就不用导xls(03)、xlsx(07),否则会冲突

easyExcel 写

DemoData.java

package com.lm.easy;

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

import java.util.Date;

@Data
public class DemoData {
    @ExcelProperty("字符串标题")
    private String string;
    @ExcelProperty("日期标题")
    private Date date;
    @ExcelProperty("数字标题")
    private Double doubleData;
    /**
     * 忽略这个字段
     */
    @ExcelIgnore
    private String ignore;
}

EasyTest.java

package com.lm.easy;

import com.alibaba.excel.EasyExcel;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class EasyTest {

    private List<DemoData> data() {
        List<DemoData> list = new ArrayList<DemoData>();
        for (int i = 0; i < 10; i++) {
            DemoData data = new DemoData();
            data.setString("字符串" + i);
            data.setDate(new Date());
            data.setDoubleData(0.56);
            list.add(data);
        }
        return list;
    }

    //根据list 写入excel
    @Test
    public void simpleWrite() {
        //存储路径
        String PATH = "C:/Users/Lenovo/Desktop/POI/";

        String fileName = PATH + "EasyExcel.xlsx";
        // 这里 需要指定写用哪个class去写,然后写到第一个sheet,名字为模板 然后文件流会自动关闭
        // 如果这里想使用03 则 传入excelType参数即可
        //参数:write(fileName,格式类)
        //sheet(表名)
        //doWrite(数据)
        EasyExcel.write(fileName, DemoData.class).sheet("模板").doWrite(data());

    }
}

EasyExcel.xlsx

POI和easyExcel操作_第5张图片

easyExcel 读

DemoDataListener.java

package com.lm.easy;

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

import java.util.ArrayList;
import java.util.List;

// 有个很重要的点 DemoDataListener 不能被spring管理,要每次读取excel都要new,然后里面用到spring可以构造方法传进去
public class DemoDataListener extends AnalysisEventListener<DemoData> {
    private static final Logger LOGGER = LoggerFactory.getLogger(DemoDataListener.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;
    List<DemoData> list = new ArrayList<DemoData>();
    /**
     * 假设这个是一个DAO,当然有业务逻辑这个也可以是一个service。当然如果不用存储这个对象没用。
     */
    private DemoDAO demoDAO;
    public DemoDataListener() {
        // 这里是demo,所以随便new一个。实际使用如果到了spring,请使用下面的有参构造函数
        demoDAO = new DemoDAO();
    }
    /**
     * 如果使用了spring,请使用这个构造方法。每次创建Listener的时候需要把spring管理的类传进来
     *
     * @param demoDAO
     */
    public DemoDataListener(DemoDAO demoDAO) {
        this.demoDAO = demoDAO;
    }
    /**
     * 这个每一条数据解析都会来调用
     *
     * @param data
     *            one row value. Is is same as {@link AnalysisContext#readRowHolder()}
     * @param context
     */
    @Override
    public void invoke(DemoData data, AnalysisContext context) {
        System.out.println(JSON.toJSONString(data)); //控制台输出
        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
     *
     * @param context
     */
    @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();
        LOGGER.info("所有数据解析完成!");
    }
    /**
     * 加上存储数据库
     */
    private void saveData() {
        LOGGER.info("{}条数据,开始存储数据库!", list.size());
        demoDAO.save(list);//持久化
        LOGGER.info("存储数据库成功!");
    }
}

DemoDao.java

package com.lm.easy;

import java.util.List;

/**
 * 假设这个是你的DAO存储。当然还要这个类让spring管理,当然你不用需要存储,也不需要这个类。
 **/
public class DemoDAO {
    public void save(List<DemoData> list) {
        // 如果是mybatis,尽量别直接调用多次insert,自己写一个mapper里面新增一个方法batchInsert,所有数据一次性插入
    }
}

@Override 报错

Languag level 5 改为 8

POI和easyExcel操作_第6张图片

EasyTest.java

/**
 * 最简单的读
 * 

1. 创建excel对应的实体对象 参照{@link DemoData} *

2. 由于默认一行行的读取excel,所以需要创建excel一行一行的回调监听器,参照{@link DemoDataListener} *

3. 直接读即可 */ @Test public void simpleRead() { // 有个很重要的点 DemoDataListener 不能被spring管理,要每次读取excel都要new,然后里面用到spring可以构造方法传进去 // 写法1: String fileName = PATH + "EasyExcel.xlsx"; // 这里 需要指定读用哪个class去读,然后读取第一个sheet 文件流会自动关闭 EasyExcel.read(fileName, DemoData.class, new DemoDataListener()).sheet().doRead(); }

Error:java: Compilation failed: internal java compiler error

version 5 改为 8

POI和easyExcel操作_第7张图片

控制台输出

"C:\Program Files\Java\jdk1.8.0_131\bin\java.exe" ...
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
{"date":1598086056000,"doubleData":0.56,"string":"字符串0"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串1"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串2"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串3"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串4"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串5"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串6"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串7"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串8"}
{"date":1598086056000,"doubleData":0.56,"string":"字符串9"}

Process finished with exit code 0

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