ActiveMQ supports advisory messages which allows you to watch the system using regular JMS messages. Currently we have advisory messages that support

consumers, producers and connections starting and stopping
temporary destinations being created and destroyed
messages expiring on topics and queues
brokers sending messages to destinations with no consumers.
connections starting and stopping

Advisory messages can be thought as some kind of administrative channel where you receive information regarding what is happening on your JMS provider along with what's happening with producers, consumers and destinations. When you look at a broker via JMX you will see the advisory topics prefixed with ActiveMQ.Advisory..

Every Advisory has the message type 'Advisory' and some predefined message properties:

Property	Type	Description	Version
`originBrokerId`	`StringProperty`	The id of the broker where the advisory originated.	5.x
`originBrokerName`	`StringProperty`	The name of the broker where the advisory originated.	5.x
`originBrokerURL`	`StringProperty`	The first URL of the broker where the advisory originated.	5.2

In addition, some messages carry a Command object - which carries more information for the advisory - e.g.

A subscription to each of the destination returns an ActiveMQMessage. Specific DataStructure objects, e.g.,. ConsumerInfo, ProducerInfo, ConnectionInfo can be retrieved using ActiveMQMessage.getDataStructure().

F or example:

+

ActiveMQ supports advisory messages which allows you to watch the system using regular JMS messages. Currently we have advisory messages that support

consumers, producers and connections starting and stopping
temporary destinations being created and destroyed
messages expiring on topics and queues
brokers sending messages to destinations with no consumers.
connections starting and stopping

Advisory messages can be thought as some kind of administrative channel where you receive information regarding what is happening on your JMS provider along with what's happening with producers, consumers and destinations. When you look at a broker via JMX you will see the advisory topics prefixed with ActiveMQ.Advisory..

Every Advisory has the message type 'Advisory' and some predefined message properties:

Property	Type	Description	Version
`originBrokerId`	`StringProperty`	The id of the broker where the advisory originated.	5.x
`originBrokerName`	`StringProperty`	The name of the broker where the advisory originated.	5.x
`originBrokerURL`	`StringProperty`	The first URL of the broker where the advisory originated.	5.2

In addition, some messages carry a Command object, which carries additional information about the nature of the advisory, e.g., a subscription to each of the destination returns an ActiveMQMessage. Specific DataStructure objects, e.g.,. ConsumerInfo, ProducerInfo, ConnectionInfo can be retrieved using ActiveMQMessage.getDataStructure().

For example:

 Destination advisoryDestination = AdvisorySupport.getProducerAdvisoryTopic(destination)
 MessageConsumer consumer = session.createConsumer(advisoryDestination);
 consumer.setMessageListener(this);
@@ -102,15 +102,17 @@ public void onMessage(Message msg){
 

The following advisory topics are supported

Client based advisories

Tip

These are always generated.

Advisory Topics	Description	Properties	Data Structure
`ActiveMQ.Advisory.Connection`	Connection start & stop messages.		`ConnectionInfo`, `RemoveInfo`
`ActiveMQ.Advisory.Producer.Queue`	Producer start & stop messages on a Queue.	`String='producerCount'` - the number of producers	`ProducerInfo`
`ActiveMQ.Advisory.Producer.Topic`	Producer start & stop messages on a Topic.	`String='producerCount'` - the numbe r of producers	`ProducerInfo`
`ActiveMQ.Advisory.Consumer.Queue`	Consumer start & stop messages on a Queue.	`String='consumerCount'` - the number of Consumers	`ConnectionInfo`, `RemoveInfo`
`ActiveMQ.Advisory.Consumer.Topic`	Consumer start & stop messages on a Topic.	`String='consumerCount'` - the number of Consumers	`ConnectionInfo, RemoveInfo`

Note that the consumer start/stop advisory messages also have a consumerCount header to indicate the number of active consumers on the destination when the advisory message was sent. This means you can use the following selector to be notified when there are no active consumers on a given destination:

 consumerCount = 0
 
-

Destination and Message based advisories

< /tbody>

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
`ActiveMQ.Advisory.Queue`	Queue create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.Topic`	Topic create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.TempQueue`	Temporary Queue create & destroy.	`null`	DestinationInfo	`true`	`none`
`ActiveMQ.Advisory.TempTopic`	Temporary Topic create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.Expired.Queue`	Expired messages on a Queue.	`String='orignalMessageId' - the expired id`	`Message`	`true`	`none`
`ActiveMQ.Advisory.Expired.Topic`	Expired messages on a Topic.	`String='orignalMessageId'` - the expired id	`Message`	`true`	`none`
`ActiveMQ.Advisory.NoConsumer.Queue`	No c onsumer is available to process messages being sent on a Queue.	`null`	`Message`	`false`	`sendAdvisoryIfNoConsumers`
`ActiveMQ.Advisory.NoConsumer.Topic`	No consumer is available to process messages being sent on a Topic.	`null`	`Message`	`false`	`sendAdvisoryIfNoConsumers`

Tip

NoConsumer topic advisories are sent only for non-persistent messages.

New advisories in version 5.2

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
`ActiveMQ.Advisory.SlowConsumer.Queue`	Slow Queue Consumer.	`String='consumerId'` - the consumer id	`ConsumerInfo`	`false`	`advisoryForSlowConsumers`
`ActiveMQ.Advisory.SlowConsumer.Topic`	Slow Topic Consumer.	`String='consumerId'` - the consumer id	`ConsumerInfo`	`false`	`advisoryForSlowConsumers`
`ActiveMQ.Advisory.FastProducer.Queue`	Fast Queue producer.	`String='producerId'` - the producer id	`ProducerInfo`	`false`	`advisdoryForFastProducers`
`ActiveMQ.Advisory. FastProducer.Topic`	Fast Topic producer.	`String='consumerId'' - the producer id`	`ProducerInfo`	`false`	`advisdoryForFastProducers`
`ActiveMQ.Advisory.MessageDiscarded.Queue`	Message discarded.	`String='orignalMessageId'` - the discarded id	`Message`	`false`	`advisoryForDiscardingMessages`
`ActiveMQ.Advisory.MessageDiscarded.Topic`	Message discarded.	`String='orignalMessageId'` - the discarded id	`Message`	`false`	`advisoryForDiscardingMessages`
`ActiveMQ.Advisory.MessageDelivered.Queue`	Message delivered to the broker.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForDelivery`
`ActiveMQ.Advisory.MessageDelivered.Topic`	Message delivered to the broker.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForDelivery`
`ActiveMQ.Advisory.MessageConsumed.Queue`	Message consumed by a client.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForConsumed`
`ActiveMQ.Advisory.MessageConsumed.Topic`	Message consumed by a client.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForConsumed`
`ActiveMQ.Advisory.FULL`	A Usage resou rce is at its limit.	`String='usageName'` - the name of Usage resource	`null`	`false`	`advisoryWhenFull`
`ActiveMQ.Advisory.MasterBroker`	A broker is now the master in a master/slave configuration.	`null`	`null`	`true`	`none`

New Advisories in 5.4

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
`ActiveMQ.Advisory.MessageDLQd.Queue`	Message sent to DLQ.	`String='orignalMessageId'` - the delivered id	`Message`	Always on	`advisoryForConsumed`
`ActiveMQ.Advisory.MessageDLQd.Topic`	Message sent to DLQ.	`String='orignalMessageId'` - the delivered id	`Message`	Always on	`advisoryForConsumed`

Network bridge advisories

Starting with ActiveMQ version 5.5 you can watch advisory topics for events related to the status of network bridges. You can get advisory messages when the network bridge is started or stopped.

Advisory Topics	Description	properties	Data Structure	Default
`ActiveMQ.Advisory.NetworkBridge`	Network bridge being stopped or started.	`Boolean="started"` - `true` if bridge is started, `false` if it is stopped. `Boolean="createdByDuplex"`- `true` if the bridge is created by remote network connector.	`BrokerInfo` - provides data of the remote broker	Always on

Enabling Advisories Disabled by Default

The advisories that are not turned on by default (see the last column) can be enabled on a PolicyEntry in the ActiveMQ Broker Configuration - e.g. - to enable a message consumed advisory you can configure the following:

+

Destination and Message based advisories

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
`ActiveMQ.Advisory.Queue`	Queue create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.Topic`	Topic create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.TempQueue`	Temporary Queue create & destroy.	`null`	< code>DestinationInfo	`true`	`none`
`ActiveMQ.Advisory.TempTopic`	Temporary Topic create & destroy.	`null`	`DestinationInfo`	`true`	`none`
`ActiveMQ.Advisory.Expired.Queue`	Expired messages on a Queue.	`String='orignalMessa geId'` - the expired id	`Message`	`true`	`none`
`ActiveMQ.Advisory.Expired.Topic`	Expired messages on a Topic.	`String='orignalMessageId'` - the expired id	`Message`	`true`	`none`
`ActiveMQ.Advisory.NoConsumer.Queue`	No consumer is available to process messages being sent on a Queue.	`null`	`Message`	`false`	`sendAdvisoryIfNoConsumers`
`ActiveMQ.Advisory.NoConsumer.Topic`	No consumer is available to process messages being sent on a Topic.	`null`	`Message`	`false`	`sendAdvisoryIfNoConsumers`

Tip

NoConsumer topic advisories are sent only for non-persistent messages.

New advisories in version 5.2

< td colspan="1" rowspan="1" class="confluenceTd">
ActiveMQ.Advisory.SlowConsumer.Queue

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
Slow Queue Consumer.	`String='consumerId'` - the consumer id	`ConsumerInfo`	`false`	`advisoryForSlowConsumers`
`ActiveMQ.Advisory.SlowConsumer.Topic`	Slow Topic Consumer.	`String='consumerId'` - the consumer id	`ConsumerInfo`	`false`	`advisoryForSlowConsumers`
`ActiveMQ.Advisory.FastProducer.Queue`	Fast Queue producer.	`String='producerId'` - the producer id	`ProducerInfo`	`false`	`advisdoryForFastProducers`
`ActiveMQ.Advisory. FastProducer.Topic`	Fast Topic producer.	`String='consumerI d'`' - the producer id	`ProducerInfo`	`false`	`advisdoryForFastProducers`
`ActiveMQ.Advisory.MessageDiscarded.Queue`	Message discarded.	`String='orignalMessageId'` - the discarded id	`Message`	`false`	`advisoryForDiscardingMessages`
`ActiveMQ.Advisory.MessageDiscarded.Topic`	Message discarded.	`String='orignalMessageId'` - the discarded id	`Message`	`false`	`advisoryForDiscardingMessages`
`ActiveMQ.Advisory.MessageDelivered.Queue`	Message delivered to the broker.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForDelivery`
`ActiveMQ.Advisory.MessageDelivered.Topic`	Message delivered to the broker.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForDelivery`
`ActiveMQ.Advisory.MessageConsumed.Queue`	Message consumed by a client.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForConsumed`
`ActiveMQ.Advisory.MessageConsumed.Topic`	Message consumed by a client.	`String='orignalMessageId'` - the delivered id	`Message`	`false`	`advisoryForConsumed`
`ActiveMQ.Advisory.FULL`	A Usag e resource is at its limit.	`String='usageName'` - the name of Usage resource	`null`	`false`	`advisoryWhenFull`
`ActiveMQ.Advisory.MasterBroker`	A broker is now the master in a master/slave configuration.	`null`	`null`	`true`	`none`

New Advisories in 5.4

Advisory Topics	Description	Properties	Data Structure	Default	PolicyEntry Property
`ActiveMQ.Advisory.MessageDLQd.Queue`	Message sent to DLQ.	`String='orignalMessageId'` - the delivered id	`Message`	Always on	`advisoryForConsumed`
`ActiveMQ.Advisory.MessageDLQd.Topic`	Message sent to DLQ.	`String='orignalMessageId'` - the delivered id	`Message`	Always on	`advisoryForConsumed`

Network bridge advisories

Starting with ActiveMQ version 5.5 you can watch advisory topics for events related to the status of network bridges. You can get advisory messages when the network bridge is started or stopped.

Advisory Topics
Description
Properties
Data Structure
Default
ActiveMQ.Advisory.NetworkBridge
Network bridge being stopped or started.
Boolean="started" - true if bridge is started, false if it is stopped.
Boolean="createdByDuplex"- true if the bridge is created by remote network connec tor.
BrokerInfo - provides data of the remote broker
Always on

Enabling Advisories Disabled by Default

The advisories that are not turned on by default (see the last column) can be enabled on a PolicyEntry in the ActiveMQ Broker Configuration, e.g., to enable a message consumed advisory you can configure the following:

 <destinationPolicy>
-   <policyMap><policyEntries> 
-      <policyEntry topic=">" advisoryForConsumed="true"/>
-   </policyEntries></policyMap>
+    <policyMap>
+       <policyEntries> 
+           <policyEntry topic=">" advisoryForConsumed="true"/>
+       </policyEntries>
+    </policyMap>
 </destinationPolicy>
 
 

Hint

The > character matches all topics - you can use wild-card matches for setting a destination policy - see Wildcards

Disabling Advisory Messages

The use of advisory messages incurs a small overhead in terms of memory and connection resources that is related to the number of destinations in your system. In some cases it can make sense to disable all advisories.

Advisories need to be disabled both on the Broker, via XML Configuration

-<broker advisorySupport="false">...
+<broker advisorySupport="false">

or from java code:

 BrokerService broker = new BrokerService();

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