jsp下载文件时出现乱码？？？？？？？？？？？

使用jsp写了一个下载文件小程序，在运行时打开的word文挡为乱码，什么原因，大家知道吗？
代码如下：
<%@ page import="java.io.*" %>
<%@ page import="useraction.*" %>
<%@ page contentType="charset=gb2312"%>
<%

///////////////////////////////
PrintWriter printwriter = response.getWriter();
String s = request.getParameter("file");
String s1 = request.getParameter("filename");
System.out.println("文件路径："+s);
System.out.println("文件名：："+s1);
response.setContentType("appliction/msword");
response.setHeader("Content-Disposition", "attachment; filename=" + s1 + "");
FileInputStream fileinputstream = new FileInputStream(s);
FileOutputStream fileoutputstream = new FileOutputStream("d:\\a.doc");
int i;
while((i = fileinputstream.read()) != -1)
{
printwriter.write(i);
fileoutputstream.write(i);
}
fileinputstream.close();
fileoutputstream.close();
printwriter.close();
printwriter.println("<body onload=window.close()>");


%>