Static Variable Omnet++

TopologyContainer.cc

#include "TopologyContainer.h"
using namespace sdicn;

cTopology TopologyContainer::instance;
bool TopologyContainer::isInitialized = false;


void TopologyContainer::initialize() {
    TopologyContainer::instance.extractByProperty("networkNode");
    TopologyContainer::isInitialized = true;
}

void TopologyContainer::clear() {
    TopologyContainer::isInitialized = false;
}

cTopology& TopologyContainer::getInstance()
{
   if (!TopologyContainer::isInitialized) {
       TopologyContainer::initialize();
   }

   return TopologyContainer::instance;
}

TopologyContainer.h

#pragma once

#include <omnetpp.h>
using namespace omnetpp;

namespace sdicn {

class TopologyContainer {
public:
    static cTopology& getInstance();
    static void clear();

    TopologyContainer(TopologyContainer &other) {
        throw cRuntimeError("Unauthorized operation.");
    }
    void operator=(const TopologyContainer &) {
        throw cRuntimeError("Unauthorized operation.");
    }

protected:
    static cTopology instance;
    static bool isInitialized;

    TopologyContainer() { }
    static void initialize();
};

}