Encapsulates the link between the UDP channel and a CallContext. More...

Collaboration diagram for protocol.RemotePeer:

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Public Member Functions
	RemotePeer (DatagramChannel socket, String remoteUserId, InetAddress remoteAddr, int remotePort)
	Constructor for the RemotePeer object.
String	getRemoteUserId ()
	Returns remote name (remote userid) of the peer.
synchronized long	receiverIdleTime ()
	Returns elapsed time since last received packet.
synchronized void	addIncomingPDU (byte[] data)
	Adds an incoming PDUs (as bytes) to the PDUs queue.
void	run ()
	Manages the incoming PDUs stored in the PDUs queue.
void	addNewCall (CallContext call)
	Adds the new (not owned) call to the peer.
void	cleanUp ()
	Stops transmitting and c cleans up resources (local and used by the calls).
void	send (OctetBuffer pdu)
	Sends packet to remote peer over datagram channel.
Protected Attributes
Vector< byte[]>	inboundPDUs = null
	The queue of incoming PDUs from remote peer via our UDP channel.
Thread	pduReceiverThread = null
	The receiving process thread.
Package Functions
void	parsePDU (byte[] octets)
	Deals with newly received PDU octets.
Private Member Functions
synchronized void	startReceiver ()
	This method starts the receiver thread for inbound PDUs.
Private Attributes
DatagramChannel	socket = null
	The UDP channel.
CallContext	call = null
	The call context.
String	remoteUserId = null
	PBXClient's (chat server's) User ID of the remote peer.
InetAddress	remoteAddr = null
	Remote IP address where to send PDUs.
int	remotePort = -1
	Remote UDP port where to send PDUs.
volatile boolean	transmitting = false
	Indicates whether communication with peer is active or not.
long	lastReceiverTimestamp = 0
	The time-stamp of the last received PDU.

Detailed Description

Encapsulates the link between the UDP channel and a CallContext.

UDP channel receives packets from all remote peers and dispatches them to particular RemotePeer handler. RemotePeer might have multiple calls in real PBX, howerever, this implementation allows only single CallContext per RemotePeer.

Author:: Mikica B Kocic

Definition at line 19 of file RemotePeer.java.

Constructor & Destructor Documentation

protocol.RemotePeer.RemotePeer	(	DatagramChannel	socket,
		String	remoteUserId,
		InetAddress	remoteAddr,
		int	remotePort
	)

Constructor for the RemotePeer object.

Parameters:

socket	instance of DatagramChannel used for communication
remoteUserId	peer's user ID
remoteAddr	peer's IP address
remotePort	peer's UDP port listening for ours PDUs

Definition at line 56 of file RemotePeer.java.

References protocol.DatagramChannel.addNewPeer(), protocol.RemotePeer.call, protocol.RemotePeer.inboundPDUs, protocol.RemotePeer.remoteAddr, protocol.RemotePeer.remotePort, protocol.RemotePeer.remoteUserId, protocol.RemotePeer.socket, and protocol.RemotePeer.startReceiver().

    {
        this.remoteUserId = remoteUserId;
        this.remoteAddr   = remoteAddr;
        this.remotePort   = remotePort;
        
        this.call = null;

        this.inboundPDUs = new Vector<byte[]> ();
        
        synchronized( socket )
        {
            this.socket = socket;
            this.socket.addNewPeer( this );
            
            if ( this.remoteAddr != null 
                    && this.remotePort > 0 && this.remotePort <= 65535 ) 
            {
                this.startReceiver ();
            }
        }
    }

Member Function Documentation

synchronized void protocol.RemotePeer.addIncomingPDU ( byte[] data )

Adds an incoming PDUs (as bytes) to the PDUs queue.

We are still on the recv thread; this data was received by binder and passed to us via friend. The PDUs are stored in the queue and we deal with them on our own thread to relief the recv thread. In other words, this is the last thing we do on the recv thread!

Parameters:

data	The PDU octets

Definition at line 126 of file RemotePeer.java.

References protocol.RemotePeer.inboundPDUs, protocol.RemotePeer.lastReceiverTimestamp, and protocol.RemotePeer.transmitting.

Referenced by protocol.DatagramChannel.run().

    {
        if ( ! this.transmitting || data == null ) {
            return;
        }

        this.lastReceiverTimestamp = System.currentTimeMillis ();
        this.inboundPDUs.addElement( data );
        this.notifyAll ();
    }

void protocol.RemotePeer.addNewCall ( CallContext call )

Adds the new (not owned) call to the peer.

Definition at line 228 of file RemotePeer.java.

References protocol.RemotePeer.call, protocol.CallContext.setDestinationCallNumber(), and protocol.CallContext.setSourceCallNumber().

Referenced by protocol.CallContext.CallContext().

    {
        this.call = call;
        
        /* Tag the call with call numbers. 
         * Note: Tagging is hard-coded here, but this place might be a core 
         * for real PBX call-id handling.
         */
        this.call.setSourceCallNumber( 0x3141 );
        this.call.setDestinationCallNumber( 0x5926 );
    }

void protocol.RemotePeer.cleanUp ( )

Stops transmitting and c cleans up resources (local and used by the calls).

Definition at line 243 of file RemotePeer.java.

References protocol.RemotePeer.call, protocol.CallContext.cleanUp(), and protocol.RemotePeer.transmitting.

Referenced by protocol.DatagramChannel.removePeer().

    {
        if ( this.call != null )
        {
            this.call.cleanUp ();
            this.transmitting = false;
        }
    }

String protocol.RemotePeer.getRemoteUserId ( )

Returns remote name (remote userid) of the peer.

Definition at line 83 of file RemotePeer.java.

References protocol.RemotePeer.remoteUserId.

Referenced by CryptoPhoneApp.executeCommand(), CryptoPhoneApp.mainTimerEvent(), and CryptoPhoneApp.sendInstantMessage().

    {
        return remoteUserId;
    }

void protocol.RemotePeer.parsePDU ( byte[] octets ) [package]

Deals with newly received PDU octets.

This method encapsulates them into a instance of PDU class, deal with internal counters, sends an acknowledgement and notifies the PDU it has arrived.

Definition at line 200 of file RemotePeer.java.

References protocol.RemotePeer.call, protocol.ProtocolDataUnit.create(), protocol.ProtocolDataUnit.destinationCallNumber, protocol.ProtocolDataUnit.onArrivedPDU(), and protocol.ProtocolDataUnit.sourceCallNumber.

Referenced by protocol.RemotePeer.run().

    {
        if ( this.call != null && octets != null ) 
        {
            /* Parse PDU
             */
            ProtocolDataUnit pdu = ProtocolDataUnit.create( this.call, octets );

            /* Dispatch PDU if it is tagged with valid call numbers.
             * Note: Dispatching is hard-coded here, but this place might be
             * a core for real PBX call-id handling.
             */
            if ( pdu != null && pdu.destinationCallNumber == 0x5926 
                             && pdu.sourceCallNumber == 0x3141 )
            {
                pdu.onArrivedPDU ();
            }
            else if ( pdu != null )
            {
                Log.warn( "Ignored PDU with destCall# " + pdu.destinationCallNumber
                        + ", srcCalL# " + pdu.sourceCallNumber );
            }
        }
    }

synchronized long protocol.RemotePeer.receiverIdleTime ( )

Returns elapsed time since last received packet.

Definition at line 112 of file RemotePeer.java.

References protocol.RemotePeer.lastReceiverTimestamp.

Referenced by protocol.DatagramChannel.isPearDead().

    {
        return System.currentTimeMillis () - this.lastReceiverTimestamp;
    }

void protocol.RemotePeer.run ( )

Manages the incoming PDUs stored in the PDUs queue.

This thread is started by startReceiver() and run separately from the binder's receiver thread.

Definition at line 142 of file RemotePeer.java.

References protocol.RemotePeer.call, protocol.RemotePeer.inboundPDUs, protocol.RemotePeer.parsePDU(), protocol.RemotePeer.socket, and protocol.RemotePeer.transmitting.

    {
        Log.trace( "Thread started" );
        
        while ( this.transmitting )
        {
            Object[] pdusToSend = new Object[0];
            
            synchronized( this ) 
            {
                try {
                    this.wait ();
                }
                catch( InterruptedException e ) {
                    /* ignored */
                }
                
                int pduCount = this.inboundPDUs.size ();
                
                // Do some smart stuff here? (limit the take to only 20 PDUs?)
                // You'd hope that normally we'd get 1 or maybe 2 PDUs here.
                //
                if ( pduCount > 0 )
                {
                    pdusToSend = new Object[ pduCount ];
                    for ( int i = 0; i < pduCount; ++i ) {
                        pdusToSend[i] = this.inboundPDUs.elementAt(i);
                    }
                    this.inboundPDUs.removeAllElements ();
                }
            }
            
            // After releasing the lock, let's deal with the list...
            // we are now on the thread of the call, any time we waste is
            // our own.
            // should really sort these into sequence before we dispose of them.
            
            for( int i = 0; i < pdusToSend.length; ++i )
            {
                try {
                    parsePDU( (byte[]) pdusToSend[i] );
                }
                catch( Throwable e ) {
                    Log.error( "ParsePDU failed; " + e.toString () );
                    Log.where ();
                }
            }
        }
        
        this.socket = null;
        this.call = null;
    }

void protocol.RemotePeer.send ( OctetBuffer pdu )

Sends packet to remote peer over datagram channel.

Definition at line 255 of file RemotePeer.java.

References protocol.RemotePeer.remoteAddr, protocol.RemotePeer.remotePort, protocol.DatagramChannel.send(), protocol.RemotePeer.socket, and protocol.RemotePeer.transmitting.

Referenced by protocol.CallContext.send().

    {
        if ( this.transmitting ) 
        {
            this.socket.send( pdu, this.remoteAddr, this.remotePort );
        }
    }

synchronized void protocol.RemotePeer.startReceiver ( ) [private]

This method starts the receiver thread for inbound PDUs.

Definition at line 91 of file RemotePeer.java.

References protocol.RemotePeer.call, protocol.RemotePeer.lastReceiverTimestamp, protocol.RemotePeer.pduReceiverThread, protocol.RemotePeer.remoteAddr, protocol.RemotePeer.remotePort, protocol.CallContext.resetClock(), and protocol.RemotePeer.transmitting.

Referenced by protocol.RemotePeer.RemotePeer().

    {
        this.transmitting = true;

        this.lastReceiverTimestamp = System.currentTimeMillis ();
            
        this.pduReceiverThread = new Thread( this, 
                "Peer-" + remoteAddr.getHostAddress() + ":" + remotePort );
        
        this.pduReceiverThread.setPriority( Thread.MAX_PRIORITY - 1 );
        
        if ( this.call != null ) {
            this.call.resetClock ();
        }
        
        this.pduReceiverThread.start ();
    }