Txc16 Class Reference

Inheritance diagram for Txc16:

List of all members.

Protected Member Functions
virtual TicTocMsg16 *	generateMessage ()
virtual void	forwardMessage (TicTocMsg16 *msg)
virtual void	initialize ()
virtual void	handleMessage (cMessage *msg)
Private Attributes
simsignal_t	arrivalSignal

---

Detailed Description

The main problem with the previous step is that we must modify the model's code if we want to change what statistics are gathered. Statistic calculation is woven deeply into the model code which is hard to modify and understand.

OMNeT++ 4.1 provides a different mechanism called 'signals' that we can use to gather statistics. First we have to identify the events where the state of the model changes. We can emit signals at these points that carry the value of chosen state variables. This way the C++ code only emits signals, but how those signals are processed are determined only by the listeners that are attached to them.

The signals the model emits and the listeners that process them can be defined in the NED file using the 'signal' and 'statistic' property.

We will gather the same statistics as in the previous step, but notice that we will not need any private member variables to calculate these values. We will use only a single signal that is emitted when a message arrives and carries the hopcount in the message.

---

Member Function Documentation

void Txc16::forwardMessage

(

TicTocMsg16 *

msg

)

[protected, virtual]

Referenced by handleMessage().

{
    // Increment hop count.
    msg->setHopCount(msg->getHopCount()+1);

    // Same routing as before: random gate.
    int n = gateSize("gate");
    int k = intuniform(0,n-1);

    EV << "Forwarding message " << msg << " on gate[" << k << "]\n";
    send(msg, "gate$o", k);
}

TicTocMsg16 * Txc16::generateMessage

(

)

[protected, virtual]

Referenced by handleMessage(), and initialize().

{
    // Produce source and destination addresses.
    int src = getIndex();
    int n = size();
    int dest = intuniform(0,n-2);
    if (dest>=src) dest++;

    char msgname[20];
    sprintf(msgname, "tic-%d-to-%d", src, dest);

    // Create message object and set source and destination field.
    TicTocMsg16 *msg = new TicTocMsg16(msgname);
    msg->setSource(src);
    msg->setDestination(dest);
    return msg;
}

void Txc16::handleMessage

(

cMessage *

msg

)

[protected, virtual]

Reimplemented from cSimpleModule.

{
    TicTocMsg16 *ttmsg = check_and_cast<TicTocMsg16 *>(msg);

    if (ttmsg->getDestination()==getIndex())
    {
        // Message arrived
        int hopcount = ttmsg->getHopCount();
        // send a signal
        emit(arrivalSignal, hopcount);

        EV << "Message " << ttmsg << " arrived after " << hopcount << " hops.\n";
        bubble("ARRIVED, starting new one!");

        delete ttmsg;

        // Generate another one.
        EV << "Generating another message: ";
        TicTocMsg16 *newmsg = generateMessage();
        EV << newmsg << endl;
        forwardMessage(newmsg);
    }
    else
    {
        // We need to forward the message.
        forwardMessage(ttmsg);
    }
}

void Txc16::initialize

(

)

[protected, virtual]

Reimplemented from cComponent.

{
    arrivalSignal = registerSignal("arrival");
    // Module 0 sends the first message
    if (getIndex()==0)
    {
        // Boot the process scheduling the initial message as a self-message.
        TicTocMsg16 *msg = generateMessage();
        scheduleAt(0.0, msg);
    }
}

---

Member Data Documentation

simsignal_t Txc16::arrivalSignal [private]

Referenced by handleMessage(), and initialize().

---

The documentation for this class was generated from the following file:

• txc16.cc