“Hello World,” the JMX way - JMX in Action - page 25

Figure 2.1
The layers of the
JMX architecture
work together.

In this chapter, you will interact with components from each layer. From the
instrumentation layer, you will be using an MBean. MBeans are Java objects that
encapsulate a resource and expose it for management. From the agent layer, you
will use a JMX agent. Actually, you will write your own agent to contain your
MBean. And finally, from the distributed layer, you will use the HTML adapter,
which is a Java object that allows management applications to communicate with
your agent over HTML as a communication protocol. Management applications
are any applications that are interested in accessing, configuring, or manipulat-
ing manageable resources.

2.1.2 Setting up the development environment

If you don't already have the JMX RI from Sun Microsystems, download it from
http://www.java.sun.com. Download the 1.0 version of J MX . Once you have down-
loaded the zip file, extract it to your hard drive. The extracted zip file produces a
JMX parent directory containing the following directories:

contrib— Contains unsupported contributions from Sun Microsystems. For
example, Sun provides a Java RMI connector, which, like the adapters,
allows management applications to communicate with JMX agents.

jmx— Contains the JMX RI , examples, and documentation.