POI导出Excel并下载

<!-- 导出excel -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.9</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.9</version>
</dependency>

public class ExcelUtil {
@SuppressWarnings("deprecation")
public static void excelUtil(HttpServletResponse response,String[] headers,
List<InsuranceDetailsVO> InsuranceDetailsVOs)
throws IOException{
//创建HSSFWorkbook对象(excel的文档对象)
HSSFWorkbook wb = new HSSFWorkbook();
//建立新的sheet对象（excel的表单）
HSSFSheet sheet = wb.createSheet("CSRExport"); //设置列宽
sheet.setColumnWidth(0, 20*256);
sheet.setColumnWidth(1, 25*256);
sheet.setColumnWidth(2, 24*256);
.....//生成一个样式
HSSFCellStyle style1 = wb.createCellStyle(); //字体设置
HSSFFont font = wb.createFont();
font.setFontName("仿宋_GB2312");
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);//粗体显示
font.setFontHeightInPoints((short) 12);// style1.setAlignment(HSSFCellStyle.ALIGN_CENTER);
style1.setAlignment(CellStyle.ALIGN_CENTER);//水平居中
style1.setVerticalAlignment(CellStyle.VERTICAL_CENTER);//垂直居中
style1.setFont(font);
style1.setWrapText(true); HSSFRow row1=sheet.createRow(0); for (short i = 0; i < headers.length; i++) {
row1.createCell(i).setCellValue(headers[i]);
row1.getCell(i).setCellStyle(style1);
}
for (int i = 0; i < InsuranceDetailsVOs.size(); i++) {
HSSFRow row=sheet.createRow(i+1);
....这里是给每一行的每一列填充值
} String fileName = "default.xls";
try {
fileName = "LD"+DateFormatUtils.getSystemDateByYYYYMMDD()+".xls";
} catch (ParseException e1) {
e1.printStackTrace();
} //输出流
OutputStream os=null;
try {
response.reset();
response.setCharacterEncoding("UTF-8");
response.setHeader("Content-Disposition", "attachment; filename="+fileName);
// response.setContentType("application/vnd.ms-excel;charset=utf-8");
response.setContentType("application/octet-stream;charset=UTF-8"); //流输出
os = new BufferedOutputStream(response.getOutputStream());
wb.write(os);
} catch (Exception e) {
e.printStackTrace();
} finally{
if(os!=null){
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
} }}