private void test()
        {
            DBEngine <int, DBElement <int, string> > db = new DBEngine <int, DBElement <int, string> >();
            ItemFactory <int, string> itemFactory       = new ItemFactory <int, string>();
            int key = 0;

            //-----------Modify Metadata--------------------------
            "Modify metadata".title('.');
            WriteLine("\n Elements in DB :");
            db.showDB();
            key = 2;
            string name        = "Nitish";
            string description = "MS in CE";

            WriteLine("\n\n\n New Details for metadata of key {0} :", key);
            WriteLine("\n Name : {0}", name);
            WriteLine("\n Description : {0}", description);
            WriteLine();
            db.modifyMetadata(key, name, description);
            WriteLine("\n\n DB after the change :");
            db.showDB();
            WriteLine();
            "".demarcation();
            //-----------Modify Metadata--------------------------

            //-------------------Replace Value instance-----------------------
            "Replace value instance".title('.');
            WriteLine("\n\n Elements in DB :");
            DBElement <int, string> elem = itemFactory.Create();

            db.showDB();
            key = 2;
            //DBElement<int, string> elem = new DBElement<int, string>();
            elem.name      = "new element";
            elem.descr     = "new test element";
            elem.timeStamp = DateTime.Now;
            elem.children.AddRange(new List <int> {
                7, 8, 9
            });
            elem.payload = "new elem's payload";
            WriteLine("\n\n New instance for replacement for key {0}:\n", key);
            elem.showElement();
            WriteLine("\n\n Replace instance of a key :");
            db.replaceKeyInstance(key, elem);
            WriteLine("\n\n DB after the change :");
            db.showDB();
            WriteLine();
            "".demarcation();
            //-------------------Replace Value instance-----------------------
        }