导入jar包

Apache POI的maven坐标

<dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>3.17</version>
</dependency>
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>3.17</version>
</dependency>

将数据写入Excel文件

import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;public class Wan {public static void write() throws Exception{//在内存中创建一个Excel文件对象XSSFWorkbook excel = new XSSFWorkbook();//创建Sheet页XSSFSheet sheet = excel.createSheet("daye");//在Sheet页中创建行，0表示第1行XSSFRow row1 = sheet.createRow(0);//创建单元格并在单元格中设置值，单元格编号也是从0开始，1表示第2个单元格row1.createCell(1).setCellValue("姓名");row1.createCell(2).setCellValue("城市");XSSFRow row2 = sheet.createRow(1);row2.createCell(1).setCellValue("张三");row2.createCell(2).setCellValue("北京");XSSFRow row3 = sheet.createRow(2);row3.createCell(1).setCellValue("李四");row3.createCell(2).setCellValue("上海");FileOutputStream out = new FileOutputStream(new File("D:\\daye.xlsx"));//通过输出流将内存中的Excel文件写入到磁盘上excel.write(out);//关闭资源out.flush();out.close();excel.close();}public static void main(String[] args) throws Exception {write();}
}

读取Excel文件中的数据

import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;public class Wan {public static void read() throws Exception{FileInputStream in = new FileInputStream(new File("D:\\daye.xlsx"));//通过输入流读取指定的Excel文件XSSFWorkbook excel = new XSSFWorkbook(in);//获取Excel文件的第1个Sheet页XSSFSheet sheet = excel.getSheetAt(0);//获取Sheet页中的最后一行的行号int lastRowNum = sheet.getLastRowNum();for (int i = 0; i <= lastRowNum; i++) {//获取Sheet页中的行XSSFRow titleRow = sheet.getRow(i);//获取行的第2个单元格XSSFCell cell1 = titleRow.getCell(1);//获取单元格中的文本内容String cellValue1 = cell1.getStringCellValue();//获取行的第3个单元格XSSFCell cell2 = titleRow.getCell(2);//获取单元格中的文本内容String cellValue2 = cell2.getStringCellValue();System.out.println(cellValue1 + " " +cellValue2);}//关闭资源in.close();excel.close();}public static void main(String[] args) throws Exception {read();}
}