阅读下列实现文件下载的代码，找出其中有几处错误()。publicvoiddownload(Filef,HttpServletRes

阅读下列实现文件下载的代码，找出其中有几处错误（)。publicvoiddownload（Filef,HttpServletRes

阅读下列实现文件下载的代码，找出其中有几处错误()。

publicvoiddownload(Filef,HttpServletResponseresponse){

response.setContentType("application/x-msdownload");

response.setContentLength(f.length());

response.setHeader("Content-disposition","attachment;filename="+newString(fileName.getBytes("GBK"),"ISO-8859-1"));

FileInputStreamfis=newFileInputStream(f);

OutputStreamos=newFileOutputStream();

byte[]bt=newbyte[1024];

intsize=0;

while((size=fis.read(bt))!=0){

os.write(bt,0,size);

}

os.close();

fis.close();

}

A.1

B.2

C.3

D.4