Java 使用POI 实现Excel 的导出

Posted 2023-02-10 老王学Java

/**
 测试类
*/

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;  
      

  
/**
  实现方法：
*/

package excelDemo;

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 ExcelExport

/**
* @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 = ExcelExport.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();