MFC Message Only CWnd subclass

class MessageSink : public CWnd
{
public:
    MessageSink() : windowClassName(::AfxRegisterWndClass(NULL))
    {
    }

    virtual ~MessageSink()
    {
        if(GetSafeHwnd())
        {
            ::DestroyWindow(GetSafeHwnd());
        }
    }

    BOOL Create()
    {
        return CreateEx(
            NULL,
            windowClassName,
            TEXT("Message Only Window"),
            0,
            0, 0, 0, 0,
            HWND_MESSAGE,
            NULL,
            /* user data */ NULL);
    }

protected:
    DECLARE_MESSAGE_MAP()

private:
    afx_msg LRESULT OnGoesNowhereDoesNothing(WPARAM, LPARAM)
    {
        ::AfxMessageBox(TEXT(__FUNCTION__));
        return 0;
    }

    afx_msg void OnDestroy()
    {
        ::AfxMessageBox(TEXT(__FUNCTION__));
    }

    CString windowClassName;
};

BEGIN_MESSAGE_MAP(MessageSink, CWnd)
    ON_MESSAGE(WM_USER + 1, OnGoesNowhereDoesNothing)
    ON_WM_DESTROY()
END_MESSAGE_MAP()