讀文件：使用new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8"));

　　　　 StringBuffer strBuf = new StringBuffer();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8"));
        int tempchar;
        while ((tempchar = bufferedReader.read()) != -1) {
            strBuf.append((char) tempchar);
        }
        bufferedReader.close();
        return strBuf.toString();
 

寫文件：使用new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), "UTF-8"));

　　　　　File file = new File(filePath + "/" + fileName);
        if (!file.exists()) {// 如果文件不存在則創建
            file.createNewFile();
        } else {
            throw new Exception("文件已存在");
        }
        // 獲取該文件的緩沖輸出流
 

        BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), "UTF-8"));
        // 寫入信息
        bufferedWriter.write(content);
        bufferedWriter.flush();// 清空緩沖區
        bufferedWriter.close();// 關閉輸出流

Java讀寫文件，中文亂碼解決