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Design an object-oriented library management system that manages a book catalogue, physical copies (BookItems), member registration with role-based borrow limits, lending with due-date tracking and overdue fines, book reservations, and search.
The system distinguishes between a Book (catalogue entry by ISBN) and a BookItem (physical copy with barcode). Members (Student, Faculty, General) have different maximum books and lending periods. Overdue fines are calculated at a flat daily rate. Reservations notify members when a copy becomes available.
Add books to catalogue
Add book titles and physical copies (BookItems) with barcode and rack location
Search books
Search the catalogue by title, author, category, or ISBN
Issue a book
Lend a book item to a member; validate borrow limits and availability
Return a book
Accept a returned book and calculate overdue fine
Renew a book
Extend the lending period if no reservation exists
Reserve a book
Place a reservation when all copies are unavailable; notify when available
Collect fines
Track and accept payment for overdue fines
Member management
Register members (Student, Faculty, General) with different borrow limits
Before diving into code, clarify the use cases and edge cases. Understanding the problem deeply leads to better class design.
Identify the primary actions users will perform. For a parking lot: park vehicle, exit vehicle, check availability. Each becomes a method.
Who interacts with the system? Customers, admins, automated systems? Each actor type may need different interfaces.
What are the limits? Max vehicles, supported vehicle types, payment methods. Constraints drive your data structures.
What happens on overflow? Concurrent access? Payment failures? Thinking about edge cases reveals hidden complexity.
The complete explanation is included with Career and All Access. Compare it with your approach once you’ve worked through the problem.