AcDbObject: Functions Rarely Overridden

A custom class rarely overrides the following functions:

virtual Acad::ErrorStatus 
setOwnerId(AcDbObjectId objId);
 
virtual resbuf*           
xData(const char* regappName = NULL) const;
 
virtual Acad::ErrorStatus 
setXData(const resbuf* xdata);
 
virtual void 
addPersistentReactor(AcDbObjectId objId);
 
virtual Acad::ErrorStatus 
removePersistentReactor(AcDbObjectId objId);
 
virtual void              
cancelled(const AcDbObject* dbObj);
 
virtual void              
copied(const AcDbObject* dbObj,
       const AcDbObject* newObj);
 
virtual void              
erased(const AcDbObject* dbObj,
       Adesk::Boolean pErasing = true);
 
virtual void              
goodbye(const AcDbObject* dbObj);
 
virtual void              
openedForModify(const AcDbObject* dbObj);
 
virtual void              
modified(const AcDbObject* dbObj);
 
virtual void              
modifyUndone(const AcDbObject* dbObj);
 
virtual void              
modifiedXData(const AcDbObject* dbObj);
 
virtual void              
unappended(const AcDbObject* dbObj);
 
virtual void              
objectClosed(const AcDbObjectId objId);
 
virtual void              
modifiedGraphics(const AcDbEntity* dbEnt);