JAVA 读文件和写文件乱码问题

StringBuilder result = new StringBuilder();BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream(filename), "UTF-8"));String s = null;            while((s = bufferedReader.readLine())!=null){                result.append(s+"\r\n");            }            bufferedReader.close();                System.out.println(result.toString());            //把name下的文件内容写入main内            //FileWriter fw = new FileWriter(filemain,false);            BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(filemain),"UTF-8"));            bw.write(result.toString());            bw.flush();            bw.close();