question: public CircuitBreakerBuilder counterSlidingWindow ( Duration counterSlidingWindow ) { requireNonNull ( counterSlidingWindow , "counterSlidingWindow" ) ; if ( counterSlidingWindow . isNegative ( ) || counterSlidingWindow . isZero ( ) ) { throw new IllegalArgumentException ( "counterSlidingWindow: " + counterSlidingWindow + " (expected: > 0)" ) ; } this . counterSlidingWindow = counterSlidingWindow ; return this ; }
target:  Sets the time length of sliding window to accumulate the count of events.