实现文件下载

response实现文件下载

String path =this.getServletContext().getRealPath("/download/美女.jpg");
String filename = path.substring(path.lastIndexOf("\\")+1);
//如果下载文件是中文，则文件名需要经过url编码
//  response.setHeader("content-disposition", "attachment;filename=" + (filename));
response.setHeader("content-disposition", "attachment;filename=" + URLEncoder.encode(filename,"UTF-8"));

InputStream in =null;
OutputStream out = null;
try {

in = new FileInputStream(path);
int len = 0;
byte buffer[] = new byte[1024];

out =response.getOutputStream();
while ((len=in.read(buffer))>0) {
out.write(buffer,0,len);
}
}finally{
if (in !=null) {
in.close();
}
if (out !=null) {
out.close();
}
}