Excel--java POi

import java.io.File;
import java.io.FileOutputStream;
 
import org.apache.commons.io.FileUtils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 
public class PoiExpExcel {
    public static void main(String[] args) {
        String[] title={"ID","用户","密码"};
        //创建Excel工作薄
        HSSFWorkbook workbook=new HSSFWorkbook();
        //创建一个工作表sheet
        HSSFSheet sheet=workbook.createSheet();
        //创建第一行
        HSSFRow row= sheet.createRow(0);
        HSSFCell cell=null;
        //插入第一行数据
        for (int i = 0; i < title.length; i++) {
            cell=row.createCell(i);
            cell.setCellValue(title[i]);
        }
        //追加数据
        for (int i = 0; i < 10; i++) {
            HSSFRow nextrow=sheet.createRow(i);
            //第一个单元格
            HSSFCell cell2=nextrow.createCell(0);
            cell2.setCellValue("a"+i);
            //第二个单元格
            cell2=nextrow.createCell(1);
            cell2.setCellValue("小明"+i);
            //第三个单元格
            cell2=nextrow.createCell(2);
            cell2.setCellValue("123456");
        }
        //创建一个文件
        File file=new File("e:/poi_test.xls");
        try {
            file.createNewFile();
            //写入硬盘
            FileOutputStream stream=FileUtils.openOutputStream(file);
            workbook.write(stream);
            stream.close();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

这里是导出的代码 直接贴上，下面的是导入

import java.io.File;
import java.io.IOException;
 
import org.apache.commons.io.FileUtils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 
public class PoiReaderExcel {
    public static void main(String[] args) {
        File file=new File("e:/poi_test.xls");
        try {
            //创建Excel,读取文件
            HSSFWorkbook workbook=new HSSFWorkbook(FileUtils.openInputStream(file));
            //获取第一张工作表 ：通过名字获取
//            HSSFSheet sheet=workbook.getSheet("sheet0");
            //读取默认的第一张工作页
            HSSFSheet sheet=workbook.getSheetAt(0);
            //读取分步骤详细
            int FirstRowNum=sheet.getFirstRowNum();
            int LastRowNum=sheet.getLastRowNum();
            for (int i = FirstRowNum; i < LastRowNum; i++) {
                HSSFRow row=sheet.getRow(i);
                int FirstCellNum=row.getFirstCellNum();
                int LastCellNum=row.getLastCellNum();
                for (int j = FirstCellNum; j < LastCellNum; j++) {
                    HSSFCell cell=row.getCell(j);
                    System.out.print(cell.getStringCellValue()+"  ");
                }
                System.out.println();
            }
//            for (int i = 0; i < sheet.getLastRowNum(); i++) {
//                for (int j = 0; j < sheet.getRow(i).getLastCellNum(); j++) {
//                    System.out.print(sheet.getRow(i).getCell(j).getStringCellValue()+" ");
//                }
//                System.out.println();
//            }
 
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}