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We'll take a look at each layer in turn and examine how they work together. You can also review the CXF Architecture explained by Naveen Balani and Rajeev Hathi: Apache CXF Architecture Overview

Bus

The bus is a provider of shared resources to the CXF runtime. Examples for such shared resources are: wsdl managers, binding factory managers etc. The bus can easily be extended to include your own custom resources or services, or you can replace default resources like the HTTP destination factory (based on Jetty) with your own (possibly based on Tomcat).
This is made possible by dependency injection: the default bus implemenation is based on Spring, which wires the runtime components together for you.
The SpringBusFactory searches for all bean configuration files in the META-INF/cxf directories on your classpath, and builds an application context from them. The bean configuration files included in the application context construction are:

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