SOLID Java - Modular Architecture
Agent Workflow (MANDATORY)
Before ANY implementation, use TeamCreate to spawn 3 agents:
- fuse-ai-pilot:explore-codebase - Analyze existing architecture
- fuse-ai-pilot:research-expert - Verify Java docs via Context7
- fuse-ai-pilot:sniper - Post-implementation validation
DRY - Reuse Before Creating (MANDATORY)
Before writing ANY new code:
- Grep the codebase for similar interfaces, services, or logic
- Check shared locations:
modules/core/services/, modules/core/interfaces/
- If similar code exists -> extend/reuse instead of duplicate
- If code will be used by 2+ features -> create it in
modules/core/
Architecture (Modules MANDATORY)
| Layer | Location | Max Lines |
|---|
| Controllers | modules/[feature]/controllers/ | 50 |
| Services | modules/[feature]/services/ | 100 |
| Repositories | modules/[feature]/repositories/ | 100 |
| Interfaces | modules/[feature]/interfaces/ | 30 |
| Models/DTOs | modules/[feature]/models/ | 50 |
| Shared | modules/core/{services,interfaces,models}/ | - |
NEVER use flat src/ structure - always modules/[feature]/
Critical Rules (MANDATORY)
| Rule | Value |
|---|
| File limit | 100 lines (split at 90) |
| Controllers | < 50 lines, delegate to services |
| Interfaces | modules/[feature]/interfaces/ ONLY |
| Javadoc | Every public method documented |
| Records | Use for DTOs (Java 16+) |
| Sealed | Use for restricted hierarchies (Java 17+) |
Reference Guide
Concepts
Templates
Forbidden
| Anti-Pattern | Fix |
|---|
| Files > 100 lines | Split at 90 |
| Interfaces in impl files | Move to interfaces/ directory |
new ConcreteClass() in services | Use dependency injection |
Flat src/ structure | Use modules/[feature]/ |
| God classes | Split by responsibility |
