Design Patterns
If you like applying Design Patterns, every challenge here gives you a chance to practice it on a real industry brief.
- CodeIntermediateNew
Design a Domain Model for a Library Loan System (Java)
Implement, in Java 21, an Item type hierarchy (Book, AudioBook, Periodical, EquipmentLoan — each with sub-type-specific rules), Member with eligibility logic, Loan as an aggrega…
- Java
- Oo Design
- Domain Modeling
Object-Oriented Programming and Design - CodeIntermediateNew
Refactor a Tangled Java Pricing Engine With Design Patterns
Start from a provided Java 21 codebase with the legacy PricingEngine class, 38 example fixtures (input cart, expected price), and one failing test demonstrating a bug from last …
- Java
- Design Patterns
- Refactoring
Object-Oriented Programming and Design - CodeIntermediateNew
Apply SOLID Principles to a Notifications Subsystem
Read Notifier and the last 6 months of incidents touching it. Write a 4-page design document mapping each of the 5 SOLID principles to a specific change in the subsystem (Single…
- Solid Principles
- Design Patterns
- Refactoring
Software Design and Design Patterns - CodeIntermediateNew
Build a Plugin-Based Notification Framework With Observer + Factory
Implement, in Java 21: an EventBus that supports typed subscriptions, a NotificationChannel interface with concrete subtypes (Push, Email, InApp, SMS), an AbstractChannelFactory…
- Java
- Design Patterns
- Oo Design
Object-Oriented Programming and Design Practice your coursework on real scenarios.
Every challenge is shaped from real industry context — not generic exercises. The work mirrors what your degree prepares you for.
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