public AcknowledgeMode getAcknowledgeMode(AcknowledgeMode defaultValue) {
			String ackknowledgeMode = getProperty(ACK_MODE);
			if (StringUtils.hasText(ackknowledgeMode)) {
				return AcknowledgeMode.valueOf(ackknowledgeMode);
			}
			else {
				return defaultValue;
			}
		}
Whether to automatically declare the DLQ and bind it to the bus DLX.
spring-xd-messagebus-rabbit/src/main/java/org/springframework/xd/dirt/integration/rabbit/RabbitMessageBus.java