/* Thanks Amine Laaboudi for detailed explanation and effort. https://www.sololearn.com/Discuss/3240300/why-apply-method-is-not-displaying-any-output */ #include using namespace std; #include class Developer; class QA; class ITEngg; class INotification { public: virtual void apply(shared_ptr ptrEmployee) = 0; virtual void apply(shared_ptr ptrEmployee) = 0; virtual void apply(shared_ptr ptrEmployee) = 0; }; class IEmployee { public: virtual void getInfo() = 0; virtual void accept(shared_ptr ptrNotification) = 0; IEmployee(string name,int id) : m_strName(name), m_intId(id) {} protected: string m_strName; int m_intId; }; class Developer : public IEmployee, public enable_shared_from_this { public: Developer(string name, int id) : IEmployee(name,id) {} void getInfo() { cout << "A developer ---> Name : " << m_strName << " ---> ID : " << m_intId << endl; } void accept(shared_ptr ptrNotification) override { ptrNotification->apply(this->shared_from_this()); } }; class QA : public IEmployee, public enable_shared_from_this { public: QA(string name, int id) : IEmployee(name, id) {} void getInfo() { cout << "A QA ---> Name : " << m_strName << " ---> ID : " << m_intId << endl; } void accept(shared_ptr ptrNotification) override { ptrNotification->apply(this->shared_from_this()); } }; class ITEngg : public IEmployee, public enable_shared_from_this { public: ITEngg(string name, int id) : IEmployee(name, id) {} void getInfo() { cout << "A ITEngg ---> Name : " << m_strName << " ---> ID : " << m_intId << endl; } void accept(shared_ptr ptrNotification) override { ptrNotification->apply(this->shared_from_this()); } }; class MockDrill : public INotification { public: void apply(shared_ptr ptrEmployee) override { cout << " Got emergency notification and going to assembly area 1 : My details are : "; ptrEmployee->getInfo(); } void apply(shared_ptr ptrEmployee) override { cout << " Got emergency notification and going to assembly area 2 : My details are : "; ptrEmployee->getInfo(); } void apply(shared_ptr ptrEmployee) override { cout << " Got notification but I am aware by management about mock drill and would continue critical maintenance : My details are : "; ptrEmployee->getInfo();} }; int main() { shared_ptr Dev1 = make_shared("Ketan", 1); shared_ptr QA1 = make_shared("Karan", 2); shared_ptr IT1 = make_shared("Kalpesh", 3); Dev1->getInfo(); QA1->getInfo(); IT1->getInfo(); shared_ptr ptrMockDrill = make_shared(); Dev1->accept(ptrMockDrill); QA1->accept(ptrMockDrill); IT1->accept(ptrMockDrill); return 0; }

Visitor_pattern_Corrected