Clean-Architecture

Today we focused on elevating our Library Management System to production-grade quality, with emphasis on proper domain modeling and clean architectural principles. The code changes from this session can be found here. Day 2 Summary Overview Restructured the Library Management System into a production-grade application with proper domain modeling, error handling, and service architecture. Environment & Architecture Organized codebase into clear packages: Domain entities Custom exceptions Service layer Utilities Concepts Covered Domain Modeling Refined core entities Introduced physical copy management Implemented repository pattern Separated immutable and mutable state Error Handling Created proper exception hierarchy Implemented state-based error handling Added descriptive error messages Collections and State Management Efficient storage structures Copy identification system Stream operations for data access Protected state transitions Design Patterns Repository Pattern Service Layer Interface segregation Immutable value objects Key Takeaways Clean architectural boundaries Robust error handling Type-safe operations Clear separation of concerns Next Steps Ready to explore: ...