android sdcardパスの下のファイルを読み取る方法

 
  
//   sdcard   
  
private void sdcardRead(){ 
  
String fileName = "/sdcard/my_sdcard.txt";// assets    
  
//String fileName = "/sdcard/test/my_sdcard_test.txt";// sdcard       
  
String ret = ""; 
  
try { 
  
FileInputStream fis = new FileInputStream(fileName); 
  
int len = fis.available(); 
  
byte []buffer = new byte[len]; 
   
  
fis.read(buffer);
ret = EncodingUtils.getString(buffer, "UTF-8");
fis.close();
} catch (Exception e) {
e.printStackTrace();
}
tvTXT.setText(ret);
}