Java Management Extensions

Controlling MBean Registration

There are times when it is necessary to perform certain activities before and after an MBean is registered and deregistered. Implementing the MBeanRegistration interface provides an MBean with four opportunities (i.e., callbacks) to perform additional processing. The MBeanRegistration interface is defined as:

public interface MBeanRegistration {
  
  public ObjectName preRegister(MBeanServer server, ObjectName name)
    throws java.lang.Exception;
  
  public void postRegister(Boolean registrationDone);
  
  public void preDeregister(  )
    throws java.lang.Exception;
  
  public void postDeregister(  );
}

Another advantage of implementing this interface is that the MBean itself can generate its own object name in preRegister( ) , which is invoked prior to registering the MBean. The first opportunity an MBean has to perform any additional processing is in preRegister( ), which takes two parameters. The first parameter, server , is a reference to the MBean server in which the MBean will be registered, allowing an MBean to maintain a reference to its MBean server. The second parameter, name , is the object name of the MBean. The specification does not mention anything about the behavior of this method, other than that it is invoked prior to an MBean being registered. However, looking through the RI, it is clear that the designers of JMX intended that if the name parameter is null, the MBean will generate its own object name. Otherwise, name is returned unchanged.

Once the MBean ...