C++ Namespaces

I am testing this simple C++ namespace in netbeans.

I have this namespace.... in a ANameSpace.h file...
#ifndef ANAMESPACE_H
#define      ANAMESPACE_H

namespace ANameSpace
{
    class AClass
    {
    public:
         AClass() {
     this->aValue = 0;
}

 AClass(const AClass& orig) {
}

void  aMethod(int inValue){
    this->aValue = inValue;
}

  ~AClass() {
}
       
    private:
        int aValue;
    };
}

#endif      /* ANAMESPACE_H */



Then I have a small main() like this....

#include <cstdlib>
 
using namespace std;
using namespace ANameSpace;

int main(int argc, char** argv)
{
  ANameSpace::AClass aClass;
       
  return 0;
}

I am getting abuild error at line : using namespace ANameSpace;
main.cpp:19: error: `ANameSpace' has not been declared

and also in line : ANameSpace::AClass aClass;

 `ANameSpace' has not been declared