public T getUp ( ) { if ( navigator < 0 ) { return null ; } if ( navigator == 0 ) { try { return ( T ) ( items [ navigator ] ) ; } finally { if ( wasFullAtleastOnce ) { navigator = size - 1 ; } else { navigator = emptyItemIndex - 1 ; } } } return ( T ) ( items [ navigator -- ] ) ; }
Think of this method conceptually as navigating using down up in history list of commands .