public static String convertBytesToGBInStr(Long size){
  if (size == null) {
    return String.format("0");
  }
  return String.format("%.2f",(size / (double)GB));
}

public static String convertBytesToGBInStr ( Long size ) { if ( size == null ) { return String . format ( "0" ) ; } return String . format ( "%.2f" , ( size / ( double ) GB ) ) ; }
convert the bytes to 2 - digit decimal value after precision . ex : 1376787345l bytes = > 1 . 28gb
