alivirgo Spring Boot Services AI Skill Guide
Overview & Engine Architecture
Spring Boot auto-configures a Spring application from starters on the classpath. Components are wired by dependency injection; web apps expose controllers or WebFlux handlers. Agents keep configuration in application.yml profiles, validate request bodies with Bean Validation, and use test slices (@WebMvcTest, @DataJpaTest) instead of only full-context boot tests.
Starters -> Auto-config -> ApplicationContext
|
Controllers / Services / Repositories
|
Embedded Tomcat (default servlet)
When to use this skill
- Creating Java REST services with Spring Boot
- Structuring packages (controller/service/repository)
- Configuring profiles for local vs prod
- Writing focused MVC or JPA tests
Operational directives
- Prefer constructor injection over field
@Autowired. - Use
@Valid+ constraint annotations on DTOs; return problem details on failure. - Externalize secrets via env / secrets manager - not checked-in YAML.
- Enable Actuator carefully; lock down sensitive endpoints in prod.
- Match Java LTS version to the Spring Boot generation in use.
Controller sketch
@RestController
@RequestMapping("/api/items")
public class ItemController {
private final ItemService items;
public ItemController(ItemService items) {
this.items = items;
}
@PostMapping
@ResponseStatus(HttpStatus.CREATED)
public ItemResponse create(@Valid @RequestBody ItemRequest body) {
return items.create(body);
}
}
public record ItemRequest(
@NotBlank @Size(max = 64) String sku,
@Min(0) int qty
) {}
Commands
./mvnw spring-boot:run
./gradlew bootRun
./mvnw -Dtest=ItemControllerTest test
java -jar target/app.jar --spring.profiles.active=prod
Common pitfalls
| Pitfall | Why it hurts | Fix |
|---|---|---|
| Field injection | Hard to test | Constructor injection |
God @SpringBootTest only |
Slow CI | Test slices |
| Open Actuator in prod | Info leak | Secure / disable |
| Business logic in controllers | Unmaintainable | Service layer |
Best practices
- Use Flyway/Liquibase for schema migrations.
- Prefer records or immutable DTOs at API boundaries.
- Centralize exception handling with
@ControllerAdvice. - Structured logging with correlation IDs for request traces.
Limitations
- Reactive WebFlux is a different programming model than MVC.
- Native image (GraalVM) needs extra reachability config.
- Version upgrades across Boot majors can change defaults - read release notes.
Related skills
@kotlin- Kotlin idioms on Spring Boot@docker- packaging Boot jars@graphql-apis- Spring GraphQL when needed