Why is `Intent` from notification null?

```
Intent resultIntent = new Intent(context, myclass.class);
        resultIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
                Intent.FLAG_ACTIVITY_SINGLE_TOP);
        Bundle extras=new Bundle();
        extras.putString("key","value");
        PendingIntent resultPendingIntent =
                PendingIntent.getActivity(
                        context,
                        0,
                        resultIntent,
                        PendingIntent.FLAG_UPDATE_CURRENT
                );
            NotificationCompat.Builder n = new NotificationCompat.Builder(context)
                    .setContentTitle("test")
                    .setContentText(text)
                    .setSound(sound)
                    .setContentIntent(resultPendingIntent)
                    .setAutoCancel(true)
                    .setExtras(extras)
                    .setSmallIcon(android.R.drawable.ic_media_play);
            NotificationManager notificationManager = (NotificationManager) context.getSystemService((context.getApplicationContext().NOTIFICATION_SERVICE));
            notificationManager.notify(0, n.build());
    }

```

but in `onStart()` of myclass when i call `getintent().getExtras()` the result is **null**, why?
how can I `getExtras()` from notification Intent ?