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Exposing jmx mbeans via spring for tomcat7

I needed to expose some jmx mbeans in tomcat for nagios monitoring and was reading http://tomcat.apache.org/tomcat-7.0-doc/monitoring.html and other things but it seems its a PITA to write an expose a bean. This didnt sounded right because I wanted to make it easy for junior developers to expose jmx monitors and not deal with all this complexity. Then I landed onto http://static.springsource.org/spring/docs/2.0.x/reference/jmx.html and voila the life became easy.  It took me some time to read and understand this but exposing jmx was 5 minutes.

So all I need to do is

1) create a file spring_jmx_mbeans.xml and add

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="
     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
    
    <bean id="exporter" class="org.springframework.jmx.export.MBeanExporter" lazy-init="false">
      <property name="autodetect" value="true"></property>
      <property name="namingStrategy" ref="namingStrategy"></property>
      <property name="assembler" ref="assembler"></property>
    </bean>
   
    <bean id="attributeSource" class="org.springframework.jmx.export.annotation.AnnotationJmxAttributeSource"/>
   
    <bean id="assembler" class="org.springframework.jmx.export.assembler.MetadataMBeanInfoAssembler">
      <property name="attributeSource" ref="attributeSource"/>
    </bean>
   
    <bean id="namingStrategy" class="org.springframework.jmx.export.naming.MetadataNamingStrategy">
      <property name="attributeSource" ref="attributeSource"/>
    </bean>   
</beans>

So I am asking exporter to  auto detect beans. The auto detection strategy is annotation based discovery. The naming strategy is also annotation based.


2) Include this file into applicationContext.xml like




3) Now whatever bean you want to expose just add @ManagedResouce annotation to it. To every getter add @ManagedAttribute to it.

You can override the  name of bean and attribute and give description in these annotation.


4) to see the jmx beans I just fired up jconsole and looked at the bean.


 However this is  not available for prod so thinking of using http://code.google.com/p/jminix/ for exposing jmx over http. Will write another blog post for it.

Spring is awesome!!  I will write another blog post about spring and quartz integration as it made my life easy few days back when I did quartz HA.



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