使用Apache POI 实现导出数据到Excel 并下载到本地

原文地址：http://www.cnblogs.com/bmbm/archive/2011/12/08/2342261.html
感谢这位大神

1.首先下载poi-3.6-20091214.jar，下载地址如下：

http://download.csdn.net/detail/evangel_z/3895051
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++) 
        { 
            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(); 
        } 
    } 
} 
-------------------------我是华丽的分割线------------------------------
下面实现下载功能：
HttpServletResponse response = ServletActionContext.getResponse();
File file = new File(path);// path是根据日志路径和文件名拼接出来的
            String filename = file.getName();// 获取日志文件名称
            InputStream fis = new BufferedInputStream(new FileInputStream(path));
            byte[] buffer = new byte[fis.available()];
            fis.read(buffer);
            fis.close();
            response.reset();
            // 先去掉文件名称中的空格,然后转换编码格式为utf-8,保证不出现乱码,这个文件名称用于浏览器的下载框中自动显示的文件名
            response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.replaceAll(" ", "").getBytes("utf-8"),"iso8859-1"));
            response.addHeader("Content-Length", "" + file.length());
            OutputStream os = new BufferedOutputStream(response.getOutputStream());
            response.setContentType("application/octet-stream");
            os.write(buffer);// 输出文件
            os.flush();
            os.close();