Observer.hpp

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#ifndef DART_COMMON_OBSERVER_HPP_
#define DART_COMMON_OBSERVER_HPP_

#include <set>

namespace dart {
namespace common {

class Subject;

class Observer
{
public:
  friend class Subject;

  virtual ~Observer();

protected:
  void receiveDestructionNotification(const Subject* _subject);

  virtual void handleDestructionNotification(const Subject* _subject);

  void addSubject(const Subject* _subject);

  void removeSubject(const Subject* _subject);

  void removeAllSubjects();

  std::set<const Subject*> mSubjects;
};

} // namespace common
} // namespace dart

#endif // DART_COMMON_OBSERVER_HPP_