As Ivan said in the study guide about the Endpoint Processor -
Receives incoming request and, for instance in the case of the request being a SOAP request, processes the SOAP message to extract parameters etc.
Endpoint processors are usually part of the runtime system, as is the case with JAX-WS, but may optionally be custom written.
Meaning, its role is to physically process the
SOAP message, while the Session Facade pattern defines a higher-level business component that contains and centralizes complex interactions between lower-level business components.
Regards,
Dan