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Singleton class with static method

archana07 (3)
Hi
I am trying to implement singleton class having static method.
my requirement is as below:

A.h
Class A{
Public :
Static A* getInstance();
}

B.cpp
#include A.h
Class B : public class A{
A* A::getInstance()
{
//some code.
Return *A
}
}

D.cpp
#include B.h

A* pter = A::getInstance() // error: 'getInstance' is not a member of 'A'

please tell me what is wrong in this code.
Dudester (79)
The inheritance part of your code it should be like this:
class B : public A
archana07 (3)
The below code is a psudeo code. Since i can t share my code becasue its a confidential code.
The Code is divided into two folders :
First Folder contains : We call that folder as "Folder 1"

A.h

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Class A{
Public :
Static A* getInstance();
}


A.cpp contains nothing because its a non-concrete

B.h

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#include A.h
class B : public A
{
  // some code
};


B.cpp

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A* A::getInstance(){
    //some code.
    Return *A
}


In other folder : We call that folder as "Folder 2"

D.h

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#include B.h
class D
{
	public : 

		void Initialize();
}


D.cpp

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#include D.h

D::Initialize(){

	A* pter = A::getInstance() // error: 'getInstance' is not a member of 'A'
}





I am trying to build the code on CentOs.
As per my requirement I will build the Folder 2 first and then Folder 1...
bluecoder (763)
Hi ,
why are you defining the getInstance function in class B , you have to define the function in the class a itself (.cpp) file .
archana07 (3)
[code]
A* A::getInstance(){
A* a = new B();
Return a;
}
[\code]

class A is non concrete class....
give ur rply...
bluecoder (763)
Non Concrete classes

A non concrete class is a class that cannot  be instantiated.


Ok fine, even if it is a non concrete class .
The class define nation should be in the class (.cpp) file itself .
Last edited on
bluecoder (763)
you can do as 

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class B ;
Class A
{
    Public :
             Static A* getInstance()
           {
       
              A* a = new B();
                 Return a;

              }
};


anzarzulfiqar (3)
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class A;
class B: public A ;
Class A
{
    Public :
             Static A* getInstance()
           {
       
              A* a = new B();
                 Return a;

              }
};
moorecm (1932)
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