Xml Configuration
Using ActiveMQ Classic > Xml Configuration
We support an XML deployment descriptor for configuring the ActiveMQ Classic Message Broker. There are many things which can be configured such as
- transport connectors which consist of transport channels and wire formats
- network connectors using network channels or discovery agents
- persistence providers & locations
- custom message containers (such as last image caching etc)
So we decided that using XML would make this configuration much easier. From version 4.0 onwards we use XBean to perform the XML configuration.
For details of the XML see the Xml Reference
Be careful with broker names and URIs
Make sure you do not use any strange characters in the names of brokers as they are converted to URIs which do not allow things like underscores in them etc.
Examples
The default ActiveMQ Classic configuration: current default config.
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:amq="http://activemq.apache.org/schema/core"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://activemq.apache.org/schema/core http://activemq.apache.org/schema/core/activemq-core.xsd">
<!-- Allows us to use system properties as variables in this configuration file -->
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<value>file:${activemq.conf}/credentials.properties</value>
</property>
</bean>
<!--
The <broker> element is used to configure the ActiveMQ Classic broker.
-->
<broker xmlns="http://activemq.apache.org/schema/core" brokerName="localhost" dataDirectory="${activemq.data}">
<!--
For better performances use VM cursor and small memory limit.
For more information, see:
http://activemq.apache.org/message-cursors.html
Also, if your producer is "hanging", it's probably due to producer flow control.
For more information, see:
http://activemq.apache.org/producer-flow-control.html
-->
<destinationPolicy>
<policyMap>
<policyEntries>
<policyEntry topic=">" producerFlowControl="true">
<!-- The constantPendingMessageLimitStrategy is used to prevent
slow topic consumers to block producers and affect other consumers
by limiting the number of messages that are retained
For more information, see:
http://activemq.apache.org/slow-consumer-handling.html
-->
<pendingMessageLimitStrategy>
<constantPendingMessageLimitStrategy limit="1000"/>
</pendingMessageLimitStrategy>
</policyEntry>
<policyEntry queue=">" producerFlowControl="true" memoryLimit="1mb">
<!-- Use VM cursor for better latency
For more information, see:
http://activemq.apache.org/message-cursors.html
<pendingQueuePolicy>
<vmQueueCursor/>
</pendingQueuePolicy>
-->
</policyEntry>
</policyEntries>
</policyMap>
</destinationPolicy>
<!--
The managementContext is used to configure how ActiveMQ Classic is exposed in
JMX. By default, ActiveMQ Classic uses the MBean server that is started by
the JVM. For more information, see:
http://activemq.apache.org/jmx.html
-->
<managementContext>
<managementContext createConnector="false"/>
</managementContext>
<!--
Configure message persistence for the broker. The default persistence
mechanism is the KahaDB store (identified by the kahaDB tag).
For more information, see:
http://activemq.apache.org/persistence.html
-->
<persistenceAdapter>
<kahaDB directory="${activemq.data}/kahadb"/>
</persistenceAdapter>
<!--
The systemUsage controls the maximum amount of space the broker will
use before slowing down producers. For more information, see:
http://activemq.apache.org/producer-flow-control.html
If using ActiveMQ Classic embedded - the following limits could safely be used:
<systemUsage>
<systemUsage>
<memoryUsage>
<memoryUsage limit="20 mb"/>
</memoryUsage>
<storeUsage>
<storeUsage limit="1 gb"/>
</storeUsage>
<tempUsage>
<tempUsage limit="100 mb"/>
</tempUsage>
</systemUsage>
</systemUsage>
-->
<systemUsage>
<systemUsage>
<memoryUsage>
<memoryUsage limit="64 mb"/>
</memoryUsage>
<storeUsage>
<storeUsage limit="100 gb"/>
</storeUsage>
<tempUsage>
<tempUsage limit="50 gb"/>
</tempUsage>
</systemUsage>
</systemUsage>
<!--
The transport connectors expose ActiveMQ Classic over a given protocol to
clients and other brokers. For more information, see:
http://activemq.apache.org/configuring-transports.html
-->
<transportConnectors>
<!-- DOS protection, limit concurrent connections to 1000 and frame size to 100MB -->
<transportConnector name="openwire" uri="tcp://0.0.0.0:61616?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
<transportConnector name="amqp" uri="amqp://0.0.0.0:5672?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
</transportConnectors>
<!-- destroy the spring context on shutdown to stop jetty -->
<shutdownHooks>
<bean xmlns="http://www.springframework.org/schema/beans" class="org.apache.activemq.hooks.SpringContextHook" />
</shutdownHooks>
</broker>
<!--
Enable web consoles, REST and Ajax APIs and demos
Take a look at ${ACTIVEMQ_HOME}/conf/jetty.xml for more details
-->
<import resource="jetty.xml"/>
</beans>
From a binary distribution, from version 1.1 onwards there is an activemq script allowing you to run a Message Broker as a stand alone process from the command line easily providing the $ACTIVEMQ_HOME/bin directory is on your PATH.
AMQ 4.x
if myConfig.xml is in the classpath
activemq xbean:myConfig.xml
or to use the file path system
activemq xbean:file:../conf/myConfig.xml
AMQ 3.x
activemq myConfig.xml
Or to use the default config file its just
activemq
If you have a source distribution you can run a broker using Maven specifying one of these configuration files as follows
under the assembly module run :
maven server -Dconfig=xbean:file:src/release/conf/activemq.xml
If your classpath is set up correctly you can achieve the same thing from the command line
java org.apache.activemq.broker.Main xbean:file:src/release/conf/activemq.xml
Configuring embedded brokers
You can also use the XML Configuration to configure embedded brokers. For example using the JNDI configuration mechanism you can do the following
BrokerXmlConfigFromJNDITest
Or of you want to explicitly configure the embedded broker via Java code you can do the following
BrokerXmlConfigStartTest
User Submitted Configurations
We have a page which allows users to submit details of their configurations.
Background
Since ActiveMQ Classic has so many strategy pattern plugins for transports, wire formats, persistence and many other things, we wanted to leave the configuration format open so that you the developer can configure and extend ActiveMQ Classic in any direction you wish.
So we use the Spring XML configuration file format, which allows any beans / POJOs to be wired together and configured. However often Spring’s XML can be kinda verbose at times, so we have implemented an ActiveMQ Classic extension to the Spring XML which knows about the common, standard ActiveMQ Classic things you’re likely to do (e.g. tags like connector, wireFormat, serverTransport, persistence) - but at any time you can fall back to the normal Spring way of doing things (with tags like bean, property etc).
To see documentation of the XML file we use or to get access to the XSD/DTD see the Xml Reference
