public boolean sync()

in qpid-jms-client/src/main/java/org/apache/qpid/jms/provider/ProgressiveProviderFuture.java [48:112]
58 lines of code
14 McCabe index (conditional complexity)

    public boolean sync(long amount, TimeUnit unit) throws ProviderException {
        try {
            if (isComplete() || amount == 0) {
                failOnError();
                return true;
            }

            final long timeout = unit.toNanos(amount);
            long maxParkNanos = timeout / 8;
            maxParkNanos = maxParkNanos > 0 ? maxParkNanos : timeout;
            final long tinyParkNanos = Math.min(maxParkNanos, TINY_PARK_NANOS);
            final long smallParkNanos = Math.min(maxParkNanos, SMALL_PARK_NANOS);
            final long startTime = System.nanoTime();
            int idleCount = 0;

            if (Thread.currentThread().isInterrupted()) {
                throw new InterruptedException();
            }

            while (true) {
                final long elapsed = System.nanoTime() - startTime;
                final long diff = elapsed - timeout;

                if (diff >= 0) {
                    failOnError();
                    return isComplete();
                }

                if (isComplete()) {
                    failOnError();
                    return true;
                }

                if (idleCount < SPIN_COUNT) {
                    idleCount++;
                } else if (idleCount < YIELD_COUNT) {
                    Thread.yield();
                    idleCount++;
                } else if (idleCount < TINY_PARK_COUNT) {
                    LockSupport.parkNanos(tinyParkNanos);
                    idleCount++;
                } else if (idleCount < SMALL_PARK_COUNT) {
                    LockSupport.parkNanos(smallParkNanos);
                    idleCount++;
                } else {
                    synchronized (this) {
                        if (isComplete()) {
                            failOnError();
                            return true;
                        }

                        waiting++;
                        try {
                            wait(-diff / 1000000, (int) (-diff % 1000000));
                        } finally {
                            waiting--;
                        }
                    }
                }
            }
        } catch (InterruptedException e) {
            Thread.interrupted();
            throw ProviderExceptionSupport.createOrPassthroughFatal(e);
        }
    }