code: boolean isAvailable(long sequence)
  	{
  		int index = calculateIndex(sequence);
  		int flag = calculateAvailabilityFlag(sequence);
  		long bufferAddress = (index * SCALE) + BASE;
  		return UNSAFE.getIntVolatile(availableBuffer, bufferAddress) == flag;
  	}
docs: See {@code RingBufferProducer.isAvailable(long)}