public int compare(Message<?> message1, Message<?> message2) { MessagePriority priority1 = message1.getHeaders().getPriority(); MessagePriority priority2 = message2.getHeaders().getPriority(); priority1 = priority1 != null ? priority1 : MessagePriority.NORMAL; priority2 = priority2 != null ? priority2 : MessagePriority.NORMAL; return priority1.compareTo(priority2); } }