question: public static long addAndGet ( AtomicLong current , long toAdd ) { long u , r ; do { r = current . get ( ) ; if ( r == Long . MAX_VALUE ) { return Long . MAX_VALUE ; } u = addCap ( r , toAdd ) ; } while ( ! current . compareAndSet ( r , u ) ) ; return u ; }
target:  Concurrent addition bound to Long.MAX_VALUE. Any concurrent write will "happen" before this operation.