question: public void addNewDuration ( long duration ) { callsNumber . incrementAndGet ( ) ; total . addAndGet ( duration ) ; synchronized ( lock ) { if ( duration < minimum . longValue ( ) ) { minimum . set ( duration ) ; } if ( duration > maximum . longValue ( ) ) { maximum . set ( duration ) ; } } }
target:  Add a new operation duration to this class.  Total is updated and calls is incremented