The JMX specification does not define any type of life cycle or dependency management for MBeans. The JBoss ServiceController MBean introduces this notion. A JBoss MBean is an extension of the JMX MBean in that an MBean is expected to decouple creation from the life cycle of its service duties. This is necessary to implement any type of dependency management. For example, if you are writing an MBean that needs a JNDI naming service to be able to function, your MBean needs to be told when its dependencies are satisfied. This ranges from difficult to impossible to do if the only life cycle event is the MBean constructor. Therefore, JBoss introduces a service life cycle interface that describes the events a service can use to manage its behavior. The following listing shows the org.jboss.system.Service interface:

package org.jboss.system;
public interface Service
{
    public void create() throws Exception;
    public void start() throws Exception;
    public void stop();
    public void destroy();
}

The ServiceController MBean invokes the methods of the Service interface at the appropriate times of the service life cycle. We'll discuss the methods in more detail in the ServiceController section.