JDBC based Odata services - Multiple tables not showing data

Hello Experts, I am creating odata service implementation project which is JDBC based using database of SQL . After deploying project I can only see the data of first collection set  and not all collection sets. this is my service document DefaultXCustomerXProductsXSales_Order_HeaderXSales_Order_LineXCustomer_Shipto when I can get the data for  XCustomer collection,but not all other 4 collections.It is showing me following error. Could not instantiate data provider based on class null Can anybody help me to solve this error. Thanks and regards, Shweta Lodhe