How to load FileInputStream in a septate class
EditText eTuser;
EditText eTpassword;
CheckBox StaySignedIn;
Button bSubmit;
String user;
String pass;
FileOutputStream fos;
FileInputStream fis = null;
String FILENAME = "userandpass";

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.login);
    eTuser = (EditText) findViewById(R.id.eTuser);
    eTpassword = (EditText) findViewById(R.id.eTpassword);
    StaySignedIn = (CheckBox) findViewById(R.id.Cbstay);
    bSubmit = (Button) findViewById(R.id.bLogIn);
    bSubmit.setOnClickListener(this);
    File file = getBaseContext().getFileStreamPath(FILENAME);
    if (file.exists()) {
    Intent i = new Intent(LogIn.this, ChatService.class);
    startActivity(i);
    }
    //if if file exist close bracket
    try {
        fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
        fos.close();
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } // end of catch bracket
catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } // end of catch

} // create ends here

public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {

    case R.id.bLogIn:
        String user = eTuser.getText().toString();
        String pass = eTpassword.getText().toString();
        Bundle userandpass = new Bundle();
        userandpass.putString("user", user);
        userandpass.putString("pass", pass);
        Intent login = new Intent(LogIn.this, logincheck.class);
        login.putExtra("pass", user);
        login.putExtra("user", pass);
        startActivity(login);

        if(StaySignedIn.isChecked());
        String userstaysignedin = eTuser.getText().toString();
        String passstaysignedin = eTpassword.getText().toString();
        try {
        fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
        fos.write(userstaysignedin.getBytes());
        fos.write(passstaysignedin.getBytes());
        fos.close();
        } catch(IOException e) {
            // end of try bracket, before the Catch IOExceptions e.
            e.printStackTrace();




        } // end of catch bracket


    } // switch and case ends here
}// Click ends here

 }// main class ends here

fis = openFileInput(FILENAME);
            byte[] dataArray = new byte[fis.available()];
            while (fis.read(dataArray) != -1); {
                //while statement }