用JSP读取文件并显示时出现乱码的解决过程

今天用JSP读取本地文件（中文）并显示到浏览器上时出现乱码，开始觉得是JSP的问题：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
就改这里面的的charset和pageEncoding，结果改了仍是错，而后直觉告诉我错误不是这里，应该是读文件的问题，改正事后果真一切正常。

<%

String spath = request.getRealPath("/");
String sfilename = "test.txt";

FileInputStream fr = null;
File file = new File(spath+sfilename);
BufferedReader brd = null;
fr = new FileInputStream(file);
brd = new BufferedReader(new InputStreamReader(fr,"UTF-8"));
StringBuffer resultBuffer = new StringBuffer();
while(brd.readLine() != null)
{
String fileline = brd.readLine();
    resultBuffer = resultBuffer.append(fileline);
}
out.println(resultBuffer);