To ensure functionality and security, the developed code I created uses input validation and unit testing. Methods enforce constraints on IDs, names, dates, and descriptions, preventing invalid data entry. Tests (e.g., ContactServiceTest, AppointmentServiceTest) validate functionality under various edge cases and error conditions. Security is enhanced by using non-modifiable IDs, limiting updates to only certain fields, and preventing invalid states, such as past dates in appointments.
User needs are reflected in the clear constraints for inputs, such as character limits, required formats, and non-null values. The program supports adding, updating, and deleting tasks, contacts, and appointments through services that dynamically handle changes. Features like unique ID generation and error handling ensure scalability and reliability. Tests simulate real-world scenarios to confirm that user expectations, such as updating partial fields or validating dates, are met.
The design approach follows a modular structure where each entity (tasks, contacts, appointments) is separated into individual classes with specific responsibilities. Services manage business logic, while tests ensure robustness. For example:
- Encapsulation protects internal state changes by validating inputs.
- Scalability is supported through unique ID generation and dynamic data storage.
- Testing-Driven Development (TDD) ensures that features are validated before deployment.
This approach allows flexibility for future extensions, such as adding new fields or enhancing security, without breaking existing functionality.