Java读取超大文本文件

File file = new File(filepath);     
BufferedInputStream fis = new BufferedInputStream(new FileInputStream(file));      
BufferedReader reader = new BufferedReader(new InputStreamReader(fis,"utf-8"),5*1024*1024);// 用5M的缓冲读取文本文件    
          
String line = "";  
while((line = reader.readLine()) != null){  
//TODO: write your business  
}