question: private boolean checkCurrentKeyAge ( ) throws NumberFormatException { long currentTokenKeyTS = Long . parseLong ( _cachedTokenKeysBundle . getCurrentKeyEntry ( ) ) ; long now = System . currentTimeMillis ( ) ; long diff = now - currentTokenKeyTS ; if ( diff >= _keyRotationIntervalInMsecs ) { return false ; } return true ; }
target:  Looks at the current key timestamp. If it is older than rotation interval, return false.