Introduction - If you have any usage issues, please Google them yourself
System features list: 1, the member registration: input member name, member name should be the only 2, the member list: display all member 3, delete information: according to input the User name to delete, add 4 items: input name of commodity, price, description and goods list: display all commodities information 6, delete: 7, placing orders according to brand name to delete a single commodity (to buy) : enter the User name, name of commodity, quantity for Order operation, Order list: display all orders (including the information such as User name, trade name, Order number) system design phase: 1 first find the noun: (Domain Model) (entity) : member - > User, commodity - > Product, Order - > Order 2 business logic implementation