This inheritance list is sorted roughly, but not completely, alphabetically:

[detail level 123]

CClient
CCommunicator
▼CE
CNotSupportedException
▼CException
CDataFlowException
CInvalidArgumentException
CLengthException
CNotSupportedException
CSocketException
CUnexpectedValueException
▼CI
CInvalidArgumentException
▼CL
CLengthException
CQuery
CRegistry
▼CU
CUnexpectedValueException
▼CArrayAccess
CResponseCollection
▼CCountable
▼CMessage
CRequest
CResponse
CResponseCollection
CUtil
▼CIteratorAggregate
CMessage
▼CRuntimeException
CDataFlowException
CSocketException
▼CSeekableIterator
CResponseCollection