Designing Hexagonal Architecture With Java Pdf -

// domain/spi/ProductRepository.java (Outgoing Port) package com.example.domain.spi; import com.example.domain.model.Product; import java.util.Optional;

@RequiredArgsConstructor public class CreateProductService implements CreateProductUseCase private final ProductRepository productRepository; // depends on outgoing port designing hexagonal architecture with java pdf

record CreateProductCommand(String name, double price, String currency) {} } // domain/spi/ProductRepository

// Note: ProductJpaEntity is a JPA-annotated class that the domain never sees. // bootstrap/Application.java @SpringBootApplication public class Application public static void main(String[] args) SpringApplication.run(Application.class, args); // Manual wiring if not using Spring's @Autowired on fields @Bean public CreateProductService createProductService(ProductRepository repo) return new CreateProductService(repo); designing hexagonal architecture with java pdf

Instead of a traditional layered architecture (where the UI depends on Business depends on Data), Hexagonal Architecture places the at the center. External systems interact with the domain through ports (interfaces) and adapters (implementations).

@PostMapping("/products") public Product createProduct(@RequestBody CreateProductCommand command) return createProductUseCase.execute(command);

Driving Adapter (REST) → Incoming Port (Interface) → Application Service → Outgoing Port (Interface) ← Driven Adapter (JPA)