The problem that occurs when reading a file from the internal memory of the android

I ran into a problem with the openfileinput class. First, I save my username and password in a file. On a successful login, I will save and navigate to the internal home screen. The problem is that I log out or close the application and open the application again, which I can read data, but when I convert it to String, I get Out as AAAAAA (each 4 bytes). Upon successful login to the main screen, I can read it correctly. I get this output before logging in.

This is something like: storing username and password in android internal memory.

Yours faithfully:

Jayant Gande