Dynamic Client Proxies are an important part of the AMX API, and enhance ease-of-use for the programmer.
JMX MBeans can be used directly by an MBeanServerConnection (see http://java.sun.com/j2se/1.5.0/docs/api/javax/management/MBeanServerConnection.html) to the server. However, client proxies greatly simplify access to Attributes and operations on MBeans, offering get/set methods and type-safe invocation of operations. Compiling against the AMX interfaces means that compile-time checking is performed, as opposed to server-side runtime checking, when invoked generically through MBeanServerConnection.
See the API documentation for the com.sun.appserv.management package and its sub-packages for more information about using proxies. The API documentation explains the use of AMX with proxies. If you are using JMX directly (for example, by usingMBeanServerConnection), the return type, argument types, and method names might vary as needed for the difference between a strongly-typed proxy interface and generic MBeanServerConnection/ObjectName interface.