文件下载firefox浏览器和chrom浏览器中文名不显示问题

/**
 *文件下载firefox浏览器中文名不显示问题 
 */
public class ServletDemo5 extends HttpServlet {
private static final long serialVersionUID = 1L;


protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
response.setContentType("text/html; charset=UTF-8");

//文件下载中文文件名不显示的问题
String path = this.getServletContext().getRealPath("/你好.jpg");//获取文件的绝对路径
String filename = path.substring(path.lastIndexOf("\\")+1); //截取文件名
String displayName = URLEncoder.encode(filename,"utf-8");//用utf-8的格式编码
if ("FF".equals(getBrowser(request))) {  
            // 针对火狐浏览器处理方式不一样了  
            displayName = new String(filename.getBytes("UTF-8"),  
                    "iso-8859-1");  
        }  
response.setHeader("content-disposition", "attachment;filename="+displayName);
InputStream in = new FileInputStream(path);
ServletOutputStream os = response.getOutputStream();
byte[] b = new byte[1024];
int len = 0;
while((len = in.read(b))>0){
os.write(b,0,len);
}
}


// 以下为服务器端判断客户端浏览器类型的方法  
    private String getBrowser(HttpServletRequest request) {  
        String UserAgent = request.getHeader("USER-AGENT").toLowerCase();  
        if (UserAgent != null) {  
            if (UserAgent.indexOf("msie") >= 0)  
                return "IE";  
            if (UserAgent.indexOf("firefox") >= 0)  
                return "FF";  
            if (UserAgent.indexOf("safari") >= 0)  
                return "SF";  
        }  
        return null;  
    }  


protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}


}