java读写大文件

java读写2G以上的大文件（推荐使用以下方法）

     static String sourceFilePath = "H:\\DataSource-ready\\question.json" ;
     static String distFilePath = "H:\\DataSource-ready\\separate\\" ;

     public static void main( String[] args )
     {
         SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//设置日期格式
         System.out.println("开始时间" + sdf.format(new Date()));// new Date()为获取当前系统时间

         long timer = System.currentTimeMillis();
         try {
             File file = new File(sourceFilePath);
             BufferedInputStream fis = new BufferedInputStream(new FileInputStream(file));
             BufferedReader reader = new BufferedReader(new InputStreamReader(fis,"utf-8"),7*1024*1024);// 用7M的缓冲读取文本文件  

             int count = 1 ;
             String outputFile = distFilePath + count + ".json" ;
             FileWriter fw = new FileWriter(outputFile);
             String line = "";
             while((line = reader.readLine()) != null){
                 if ( line.contains("},") ) {
                     line = line.replace("},", "}") ;
                     fw.append(line + "\r");
                     fw.flush();
                     fw.close();
                     count ++ ;
                     outputFile = distFilePath + count + ".json" ;
                     fw = new FileWriter(outputFile);
                 }
                 else {
                     fw.append(line + "\r");
                 }
             }
             reader.close();
             fw.flush();
             fw.close();
         } catch (IOException e) {
             System.out.println("读写文件失败!");
             e.printStackTrace();
         }
         timer = System.currentTimeMillis() - timer;
         System.out.println("处理时间：" + timer + " 毫秒");
         System.out.println("结束时间：" + sdf.format(new Date()));
     }

共同学习，共同进步，若有补充，欢迎指出，谢谢！