“Hello World,” the JMX way - JMX in Action - page 28

An important item to notice is the package statement. All examples in this chap-
ter are in the package jmxbook.ch2 , and each chapter will package its examples
accordingly (for example, jmxbook.ch3 for chapter 3).
The HelloWorldMBean interface declares a getter ( getGreeting() ) and setter
( setGreeting() ), as well as a printGreeting() method. You'll use the printGreet-
ing() method later to display the MBean's greeting value.
Listing 2.1 shows the implementation of the interface.

Listing 2.1 HelloWorld.java

package jmxbook.ch2;

public class HelloWorld implements HelloWorldMBean
{

Implements
HelloWorldMBean
interface

private String greeting = null;

public HelloWorld()
{
this.greeting = "Hello World! I am a Standard MBean";
}

public HelloWorld( String greeting )
{
this.greeting = greeting;
}

public void setGreeting( String greeting )
{
this.greeting = greeting;
}

public String getGreeting()
{
return greeting;
}

public void printGreeting()
{
System.out.println( greeting );
}

}

And with that, you have created your first MBean. Now, in order to test the
MBean, you need to create a JMX agent to contain it. The next section discusses
the creation of the HelloAgent class. After creating your agent, you can begin
using the MBean.