Dynamic Programming Issues

An MBean is a manageable resource that exposes a specific management interface. The name dynamic MBean refers to the fact that the interface is revealed at runtime, as opposed to through the introspection of static class names. The term dynamic is not meant to imply that the MBean can dynamically change its management interface. The management architecture defined by JMX and implemented in the Java Dynamic Management Kit does not support MBeans whose management interface is modified during runtime.

This is not an issue with standard MBeans which would need to be recompiled in order to change their interface. However, dynamic MBeans could be programmed so that their interface description and their generic getters, setters and the invoker have a different behavior at different times. In practice, this type of MBean could be created but it couldn't be managed after any change of interface.

As a rule, the value returned by the MBeanInfo method of a dynamic MBean, and the corresponding behavior of getters, setters and the invoker, must never change over the lifetime of a given instance of the MBean. However, it is permissible to have the same dynamic MBean class expose different management interfaces depending upon the instantiation conditions. This would be a valid MBean, since the agent architecture manages object instances, not class types. It would also be a very advanced MBean for a complex management solution, beyond the scope of this tutorial.