public static String generateRandomKey ( Random rand , int length ) { int numKeyChars = KEY_CHARS . length ( ) ; StringBuilder buf = new StringBuilder ( ) ; for ( int ii = 0 ; ii < length ; ii ++ ) { buf . append ( KEY_CHARS . charAt ( rand . nextInt ( numKeyChars ) ) ) ; } return buf . toString ( ) ; }
Return a key of the given length that contains random numbers .