JavaEE Servlet发送文件给前端

response.setHeader("Content-Disposition", "attachment;filename=VakudateCode.jar");

InputStream ins=getServletContext().getResourceAsStream("/WEB-INF/ValidateCode.jar");

OutputStream out=response.getOutputStream();

byte[] bys=new byte[1024];

int len=0;

while((len=ins.read(bys))>0){


out.write(bys, 0, len);

out.flush();



}