Swapping a PostgreSQL database for MongoDB requires changing only the adapter layer; the core business logic remains untouched.
Ports act as the gateway into and out of the core domain. In Java, ports are represented as standard Java interfaces.
public class AuthenticationApplicationService private final AuthenticationService authenticationService; private final UserRepository userRepository; Swapping a PostgreSQL database for MongoDB requires changing
package ports.inbound; import domain.Order; import java.util.UUID; public interface CreateOrderUseCase UUID createOrder(String product, double price); Use code with caution.
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The application service coordinates the interaction between the ports and adapters:
What you plan to build with (Spring Boot, Quarkus, Micronaut, etc.)? let's consider a simple feature: .
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This is where the swoops in to save the day. This guide serves as your starting point. We will explore the anatomy of hexagonal design, examine its master guide, and investigate the vibrant ecosystem of practical resources and examples surrounding it.
To illustrate the design of a hexagonal architecture with Java, let's consider a simple feature: .