javax.sip
Interfaces 
ClientTransaction
Dialog
ListeningPoint
ServerTransaction
SipListener
SipProvider
SipStack
Transaction
Classes 
DialogState
RequestEvent
ResponseEvent
SipFactory
Timeout
TimeoutEvent
TransactionState
Exceptions 
InvalidArgumentException
ObjectInUseException
PeerUnavailableException
SipException
TransactionAlreadyExistsException
TransactionDoesNotExistException
TransactionUnavailableException
TransportNotSupportedException