abstract class – Java Abtract Store

Hello, I am an ISC student and I have this project that I do not know how to do abstractly
A SOAD furniture chain aims to automate its management of furniture, staff and sales. This will include all
branches that are part of the franchise of this company.
For now, three branches will be considered, which will share the database on furniture and thus have a mobility of sales.
However, each branch will have its own employees, all the agencies having the same type of information as their employees,
ability to establish staff exchanges between agencies. The data of the workers are RFC, Name, Name,
Date of birth, last education, month sales $ and salary.
As far as furniture is concerned, we already have a database of the furniture processed in this chain and an established stock for each
The furniture The latter must decrease with sales and must be updated to reload the furniture sold.
The operations that the system will contain are as follows:
at. Sales What will be recorded by each branch to have a record of whoever sells the most. This information must
Provide the system as a result of the sales recordings made. This then leads to having an extra table
record the sales made by the branches and thus keep a record of the sales and the authors of the sales.
b. Employees All agencies contain High, Low and Listings. However, branch 1 performs a list ordered by
RFC, branch 2 is a general list, and branch 3, the list is sorted by paternal last name.
at. In branch 2, you can only have 5 employees, because it is a very small group, so the layoffs are limited to that. In
Branches 1 and 3 change no problem because they can have as many employees as needed.