- shopName

- address

- contactNo

+ manageStock()

+ manageCustomer()

+ manageBilling()

+ manageRepair()

- stockId

- itemName

- brand

- quantity

- price

+ addItem()

+ updateItem()

+ deleteItem()

- customerId

- name

- phoneNo

- email

- address

+ addCustomer()

+ updateCustomer()

+ viewCustomer()

- repairId

- deviceType

- issueDesc

- status

- cost

+ createRepair()

+ updateStatus()

+ closeRepair()

- billId

- date

- totalAmount

- paymentMethod

+ createBill()

+ viewBill()

+ printBill()