@ManagedResource is used to annotate a POJO as a MBean. @ManagedAttribute i used to expose a property getter and setter.
How to instrument MBean:
Fire up a Java Visual VM from ...\java\jdk1.8.0_25\bin\jvisualvm.exe, then from menu Tools/Plugins, install VisualVM-JConsole and VisualVM-MBeans, After that, MBeans are visible after server is started. From MBeans tab, MBeans->Soccer->JMX->metrics should display attributes of MBean.
How to view MBean attributes through rest API:
endpoint of http://localhost:8080/manager/jmxproxy/ will display attributes as JSON.
How to configure Tomcat to instrument MBean:
Create a setenv.bat (on Windows) or setenv.sh (on *nix) in Tomcat bin directory. Add this line in the setenv file:
export CATALINA_OPTS="-Dcom.sun.management.jmxremote.port=8090 -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false"
In tomcat-users.xml, add jmx role:
<role rolename="manager-gui"/>
<role rolename="manager-jmx"/>
<user username="tomcat" password="tomcat" roles="manager-gui,manager-jmx"/>This article is a good reference:
http://mrkimi01.blogspot.com/2014/03/jmx-tomcat-and-visualvm.html