org.jlibrtp

Class ParticipantDatabase

java.lang.Object

org.jlibrtp.ParticipantDatabase

public class ParticipantDatabase
extends java.lang.Object

The participant database maintains three hashtables with participants. The key issue is to be fast for operations that happen every time an RTP packet is sent or received. We allow linear searching in cases where we need to update participants with information. The keying is therefore usually the SSRC. In cases where we have the cname, but no SSRC is known (no SDES packet has been received), a simple hash i calculated based on the CNAME. The RTCP code should, when receiving SDES packets, check whether the participant is known and update the copy in this database with SSRC if needed.

Author:

Arne Kepp

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ParticipantDatabase(RTPSession parent) Simple constructor

Method Summary

Modifier and Type	Method and Description
protected int	addParticipant(int cameFrom, Participant p)
protected void	debugPrint()
protected Participant	getParticipant(long ssrc) Find a participant based on the ssrc
protected java.util.Enumeration<Participant>	getParticipants() Enumeration of all the participants with known ssrcs.
protected java.util.Iterator<Participant>	getUnicastReceivers() Iterator for all the unicast receivers.
protected void	removeParticipant(Participant p) Remove a participant from all tables

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ParticipantDatabase

protected ParticipantDatabase(RTPSession parent)

Simple constructor

Parameters:

parent - parent RTPSession

Method Detail

addParticipant

protected int addParticipant(int cameFrom,
                             Participant p)

Parameters:

cameFrom - 0: Application, 1: RTP packet, 2: RTCP

p - the participant

Returns:

0 if okay, -1 if not

removeParticipant

protected void removeParticipant(Participant p)

Remove a participant from all tables

Parameters:

p - the participant to be removed

getParticipant

protected Participant getParticipant(long ssrc)

Find a participant based on the ssrc

Parameters:

ssrc - of the participant to be found

Returns:

the participant, null if unknonw

getUnicastReceivers

protected java.util.Iterator<Participant> getUnicastReceivers()

Iterator for all the unicast receivers. This one is used by both RTP for sending packets, as well as RTCP.

Returns:

iterator for unicast participants

getParticipants

protected java.util.Enumeration<Participant> getParticipants()

Enumeration of all the participants with known ssrcs. This is primarily used for sending packets in multicast sessions.

Returns:

enumerator with all the participants with known SSRCs

debugPrint

protected void debugPrint()