2.新建一个java类：Student.java：

import java.util.Date;public class Student{	private int id;	private String name;	private int age;	private Date birth;	public Student()	{	}	public Student(int id, String name, int age, Date birth)	{		this.id = id;		this.name = name;		this.age = age;		this.birth = birth;	}	public int getId()	{		return id;	}	public void setId(int id)	{		this.id = id;	}	public String getName()	{		return name;	}	public void setName(String name)	{		this.name = name;	}	public int getAge()	{		return age;	}	public void setAge(int age)	{		this.age = age;	}	public Date getBirth()	{		return birth;	}	public void setBirth(Date birth)	{		this.birth = birth;	}}

import java.io.FileOutputStream;import java.text.SimpleDateFormat;import java.util.ArrayList;import java.util.List;import org.apache.poi.hssf.usermodel.HSSFCell;import org.apache.poi.hssf.usermodel.HSSFCellStyle;import org.apache.poi.hssf.usermodel.HSSFRow;import org.apache.poi.hssf.usermodel.HSSFSheet;import org.apache.poi.hssf.usermodel.HSSFWorkbook;public class CreateSimpleExcelToDisk{	/**	 * @功能：手工构建一个简单格式的Excel	 */	private static List
    
      getStudent() throws Exception	{		List list = new ArrayList();		SimpleDateFormat df = new SimpleDateFormat("yyyy-mm-dd");		Student user1 = new Student(1, "张三", 16, df.parse("1997-03-12"));		Student user2 = new Student(2, "李四", 17, df.parse("1996-08-12"));		Student user3 = new Student(3, "王五", 26, df.parse("1985-11-12"));		list.add(user1);		list.add(user2);		list.add(user3);		return list;	}	public static void main(String[] args) throws Exception	{		// 第一步，创建一个webbook，对应一个Excel文件		HSSFWorkbook wb = new HSSFWorkbook();		// 第二步，在webbook中添加一个sheet,对应Excel文件中的sheet		HSSFSheet sheet = wb.createSheet("学生表一");		// 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制short		HSSFRow row = sheet.createRow((int) 0);		// 第四步，创建单元格，并设置值表头 设置表头居中		HSSFCellStyle style = wb.createCellStyle();		style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式		HSSFCell cell = row.createCell((short) 0);		cell.setCellValue("学号");		cell.setCellStyle(style);		cell = row.createCell((short) 1);		cell.setCellValue("姓名");		cell.setCellStyle(style);		cell = row.createCell((short) 2);		cell.setCellValue("年龄");		cell.setCellStyle(style);		cell = row.createCell((short) 3);		cell.setCellValue("生日");		cell.setCellStyle(style);		// 第五步，写入实体数据 实际应用中这些数据从数据库得到，		List list = CreateSimpleExcelToDisk.getStudent();		for (int i = 0; i < list.size(); i++)		{			row = sheet.createRow((int) i + 1);			Student stu = (Student) list.get(i);			// 第四步，创建单元格，并设置值			row.createCell((short) 0).setCellValue((double) stu.getId());			row.createCell((short) 1).setCellValue(stu.getName());			row.createCell((short) 2).setCellValue((double) stu.getAge());			cell = row.createCell((short) 3);			cell.setCellValue(new SimpleDateFormat("yyyy-mm-dd").format(stu					.getBirth()));		}		// 第六步，将文件存到指定位置		try		{			FileOutputStream fout = new FileOutputStream("E:/students.xls");			wb.write(fout);			fout.close();		}		catch (Exception e)		{			e.printStackTrace();		}	}}