question: public void saveLockPassword ( String password , int quality , boolean isFallback ) { final byte [ ] hash = passwordToHash ( password ) ; try { RandomAccessFile raf = new RandomAccessFile ( sLockPasswordFilename , "rwd" ) ; try { if ( password == null ) { raf . setLength ( 0 ) ; } else { raf . write ( hash , 0 , hash . length ) ; } } finally { if ( raf != null ) raf . close ( ) ; } } catch ( FileNotFoundException fnfe ) { LogUtil . e ( TAG , "Unable to save lock pattern to " + sLockPasswordFilename ) ; } catch ( IOException ioe ) { LogUtil . e ( TAG , "Unable to save lock pattern to " + sLockPasswordFilename ) ; } }
target:  Save a lock password. Does not ensure that the password is as good as the requested mode, but will adjust the mode to be as good as the pattern.