A singleton pattern of design patterns

The singleton pattern contains only one special class of a singleton class in its core structure, guaranteeing that there is only one object in the whole system through a singleton class.

Code:

1#include <iostream>2 3 classA4 {5  Public:6     intA;7     intb;8     intC;9     StaticAInstance;Ten     StaticA *getinstance () One     { A         if(!Instance) -         { -Instance =NewA; the         } -         returnInstance; -     } - }; +  -A * A::instance =NULL; +  A voidfunct () at { -A *BB =a::getinstance (); -Std::cout << Bb->a <<Std::endl; -  -Std::cout << bb->b <<Std::endl; -  inStd::cout << bb->c <<Std::endl; - } to  +  - intMainintargcChar*argv[]) the { *A *AA =a::getinstance (); $Aa->a =1;Panax NotoginsengAa->b =3; -Aa->c =5; the funct (); +  AStd::cin.Get(); the     return 0; +}

This model uses a lot in cocos, such as the Ccdirector class.

For example, we write a tool class. Using a singleton is a good choice.

A singleton pattern of design patterns