Java 实现导出excel表 POI

1.Maven添加poi-3.16.jar包，地址如下：

https://mvnrepository.com/artifact/org.apache.poi/poi

2.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;  
    }  
  
}  

3.CreateSimpleExcelToDisk.java

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<Student> 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++)  {  
            sheet.addMergedRegion(new CellRangeAddress(1, 10, 0, 0));//指定合并区域
            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();  
        }  
    }  
}