setState(State.Blocking, State.Blocked);
                waitForState(State.Unblocked, State.Failed);
            } catch (InterruptedException e) {
                throw UncheckedException.throwAsUncheckedException(e);
            }
        }

        public void expectUnblocks(Closure action) {
            try {
                waitForState(State.Blocked);

                ThreadHandle thread = getBlockingThread();

                if ( waitForState(transport) == 2 ) {
                    // already connected
                    return null;
                }
                int before = this.connectionState.getAndSet(1);
                if ( before == 1 ) {
                    // concurrent connection attempt
                    if ( waitForState(transport) == 2 ) {
                        // finished connecting