Java Management Extensions (JMX)



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Java Management Extensions (JMX) is a framework that provides a standard way of exposing Java resources, for example, appservers, to a system management infrastructure. Using the JMX framework, a provider can implement functions to list and edit settings.

JMX also includes a notification layer that management applications can use to monitor events such as the startup of an appserver.


JMX key features


JMX architecture

The JMX architecture is structured into three layers:

Instrumentation Dictates how resources can be wrapped within special Java beans, called managed beans (MBeans).
Agent Consists of the MBean server and agents, which provide a management infrastructure. The services that are implemented include:

  • Monitor
  • Event notification
  • Timers
Management Defines how external management applications can interact with the underlying layers in terms of protocols, APIs, and so on. This layer uses an implementation of the distributed services spec (JSR-077), which is not yet part of the J2EE specification.


JMX distributed administration

The JMX architecture fits into the overall distributed administration topology of an ND environment...

Key points of this distributed administration architecture...


JMX Mbeans

WAS provides a number of MBeans, each of which has different functions and operations available. For example, an appserver MBean can expose operations such as start and stop. An application MBean can expose operations such as install and uninstall. Some JMX usage scenarios that we can encounter include:

To obtain the name of a particular MBean:


set am [$AdminControl queryNames type=ApplicationManager,process=server1,*]


am = AdminControl.queryNames('type=ApplicationManager,process=server1,*')

Each WAS runtime MBean can have attributes, operations, and notifications. The complete documentation for each MBean that is supplied with WAS is available in an HTML table that is installed in each copy of WAS v7. Under the main installation directory for WAS ND, there is the web directory. Under the web directory there is another directory called mbeanDocs. In the mbeanDocs directory there are several HTML files; one HTML file for each MBean supplied with WAS. There is also an IBM_HTTP_Server_v735.html file that ties all the individual MBean files together in a top-level navigation tree. Each MBean provides a summary of its attributes, operations, and notifications.


JMX benefits

The use of JMX for management functions in WAS provides the following benefits:

Related concepts



Related tasks

Use the wsadmin scripting objects
Getting started with scripting
Start wsadmin