gecko-dev/xpcom/glue/nsWeakReference.h

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 * The Original Code is the Mozilla browser.
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 * The Initial Developer of the Original Code is
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 * Contributor(s):
 *   Scott Collins <scc@netscape.com>
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#ifndef nsWeakReference_h__
#define nsWeakReference_h__

// nsWeakReference.h

#include "nsIWeakReference.h"
#include "nsIWeakReferenceUtils.h"

class nsWeakReference;

// Set IMETHOD_VISIBILITY to empty so that the class-level NS_COM declaration
// controls member method visibility.
#undef  IMETHOD_VISIBILITY
#define IMETHOD_VISIBILITY NS_COM_GLUE

class NS_COM_GLUE nsSupportsWeakReference : public nsISupportsWeakReference
  {
    public:
      nsSupportsWeakReference()
          : mProxy(0)
        {
          // nothing else to do here
        }

      NS_DECL_NSISUPPORTSWEAKREFERENCE

    protected:
      inline ~nsSupportsWeakReference();

    private:
      friend class nsWeakReference;

      void
      NoticeProxyDestruction()
          // ...called (only) by an |nsWeakReference| from _its_ dtor.
        {
          mProxy = 0;
        }

      nsWeakReference* mProxy;

		protected:

			void ClearWeakReferences();
			PRBool HasWeakReferences() const {return mProxy != 0;}
  };

#undef  IMETHOD_VISIBILITY
#define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN

inline
nsSupportsWeakReference::~nsSupportsWeakReference()
  {
  	ClearWeakReferences();
  }

#endif