Singleton.h

/*
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  TRADE SECRETS: ESRI PROPRIETARY AND CONFIDENTIAL
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  email: contracts@esri.com
*/

#ifndef PRTX_SINGLETON_H_
#define PRTX_SINGLETON_H_

namespace prtx {


template<typename S> class Singleton {
public:
    static S* instance() {
        if (!mInstance)
            mInstance = S::createInstance();
        return mInstance;
    }

    static S* createInstance();

protected:
    Singleton() { }
    Singleton(const Singleton&) = delete;
    Singleton& operator=(const Singleton&) = delete;
    ~Singleton() { }

private:
    static S* mInstance;
};

template<typename S> S* Singleton<S>::mInstance = 0;


} // namespace prtx


#endif /* PRTX_SINGLETON_H_ */