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Static Member Functions: its strictions
/* Static Member Functions: its strictions
A static member function does not have a this pointer.
cannot be a static and a non-static version of the same function.
A static member function may not be virtual.
static functions cannot be declared as const or volatile. */
#include <iostream>
using namespace std;
class MyClass {
static int resource;
public:
static int getResource();
void freeResource() {
resource = 0;
}
};
int MyClass::resource; // define resource
int MyClass::getResource()
{
if(resource) return 0; // resource already in use
else {
resource = 1;
return 1; // resource allocated to this object
}
}
int main()
{
MyClass myObject1, myObject2;
if(MyClass::getResource())
cout << "myObject1 has resource\n";
if(!MyClass::getResource())
cout << "myObject2 denied resource\n";
myObject1.freeResource();
if(myObject2.getResource())
cout << "myObject2 can now use resource\n";
return 0;
}
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