Mikael.s.persson: /* Singleton.cpp */

2010-12-01T02:53:43Z

‎Singleton.cpp

Daviddoria: Created page with '==Singleton.cpp== #include class Log { public: static Log* Instance() { if (!instance) // Only allow one instance of class to be…'

2010-06-23T13:14:59Z

Created page with '==Singleton.cpp== <source lang="cpp"> #include <iostream> class Log { public: static Log* Instance() { if (!instance) // Only allow one instance of class to be…'

New page

==Singleton.cpp==
<source lang="cpp">
#include <iostream>

class Log
{
public:
static Log* Instance()
{
if (!instance) // Only allow one instance of class to be generated.
{
instance = new Log;
}

return instance;

}

double val;

private:
Log(){}
Log& operator=(const Log&); //prevent assignment
Log(const Log&);//prevent copy construction

static Log* instance; //store the single instance

};

Log* Log::instance = NULL;

int main(int argc, char* argv[])
{
Log::Instance()->val = 2.0;

std::cout << "val = " << Log::Instance()->val << std::endl;;

return 0;
}

</source>

@@ Line 1: / Line 1: @@
-==Singleton.cpp==
+==Singleton.h==
 <source lang="cpp">
 class Log
+{
    public:
-     static Log* Instance()
+     static Log& Instance(); //provide static member function to access the unique instance.
-−
-      if (!instance)   // Only allow one instance of class to be generated.
-−
-        instance = new Log;
-−
-−
-      return instance;
-−
-−
      double val;
    private:
-     Log(){}
+     Log(){}; //prevent construction from outside this class' methods
      Log& operator=(const Log&); //prevent assignment
-     Log(const Log&);//prevent copy construction
+     Log(const Log&); //prevent copy construction
-    static Log* instance; //store the single instance
+};
 };
-Log* Log::instance = NULL;
+==Main.cpp==
 int main(int argc, char* argv[])
+{
-   Log::Instance()->val = 2.0;
+   Log::Instance().val = 2.0;
-   std::cout << "val = " << Log::Instance()->val << std::endl;;
+   std::cout << "val = " << Log::Instance().val << std::endl;;
-	return 0;
+  return 0;
+};
 </source>

CPP/Classes/Singleton - Revision history

Mikael.s.persson: /* Singleton.cpp */

Daviddoria: Created page with '==Singleton.cpp== #include class Log { public: static Log* Instance() { if (!instance) // Only allow one instance of class to be…'