WSDL generated client: using the CXF wsdl2java tool, you can configure
this biulder using the clientClass, port and wsdlLocation property. The
MessageProcessor will then use the generated client proxy to make service invocations.
JAX-WS service class: if the serviceClass attribute is specified, this builder
will use the JaxWsClientFactoryBean from CXF to biuld a CXF Client.
The MessageProcessor will then use this client instnace to make invocations.
The serviceClass and clientClass attributes are mutually exclusive.