I'm reviewing some code and am new to C++. What are the advantages and/or disadvantages of a SW architecture where all code is encapsulated in classes which can only have a single instance. This instance is retrieved by each class which uses it. I'll try to give short example below:
//classa.h class A { public: void foo (); ~A(); //Destructor static A& getInstance(); //Retrieve Only Instance protected: A(); // Protected Constructor }; //classa.cpp #include "classa.h" A::A() {}; //Constructor A::~A() {}; //Destructor A& A::getInstance() { static A theOnlyInstance; return theOnlyInstance; } A::foo() {}; //classb.h and classc.h include "classa.h" //Normal Stuff.. A& localRefToA //classb.cpp B::B():localRefToA(A::getInstance()) {}; //Constructor B::fooB() //Function using A's member function { localRefToA.foo(); } //classC.cpp C::C():localRefToA(A::getInstance()) {}; //Constructor C::fooC() //Function using A's member function { localRefToA.foo(); } 