Below are several class diagrams describing the major data types and hierarchy involved in the SOAP and REST APIs offered by the access layer. The diagrams are built out of the implemented java data model that backs the XML/JSON serialization within the server and bundled client library.
The structure that can be seen in XML or when using code generators that build a corresponding model ouf of WSDL may slightly differ from these diagrams, even though it's logically the same.