javaweb通用读取附件方法

String code="gb2312";
HttpServletResponse response=ServletActionContext.getResponse();

//从数据库获取附件
Attach attach=attachService.findbyid(id);


InputStream in=new FileInputStream(attach.getFilepath());
response.setContentType(attach.getFiletype()+";charset="+code);
response.setHeader("Content-Disposition","attachment;filename="+new String(attach.getFilename().getBytes("gbk"),"iso-8859-1"));
ServletOutputStream servletOutputStream=response.getOutputStream();
byte[] b = new byte[2048];
int k = 0;
while ((k = in.read(b)) != -1) {
	servletOutputStream.write(b,0,k);
}
in.close();