GH-156 - Polish example.

Add sample documentation. Reintroduce Lombok to avoid boilerplate. Use jMolecules DDD abstractions to represent aggregates. Use Scenario API in test cases.

spring-modulith-example/src/main/java/example/inventory/InventoryManagement.java

@@ -16,6 +16,7 @@
 package example.inventory;
 
 import example.order.OrderCompleted;
+import lombok.RequiredArgsConstructor;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -28,15 +29,12 @@ import org.springframework.stereotype.Service;
  * @author Oliver Drotbohm
  */
 @Service
-public class InventoryManagement {
+@RequiredArgsConstructor
+class InventoryManagement {
 
 	private static final Logger LOG = LoggerFactory.getLogger(InventoryManagement.class);
 
-	final InventoryInternal dependency;
-
-	InventoryManagement(InventoryInternal dependency) {
-		this.dependency = dependency;
-	}
+	private final InventoryInternal dependency;
 
 	@ApplicationModuleListener
 	void on(OrderCompleted event) throws InterruptedException {

spring-modulith-example/src/main/java/example/inventory/package-info.java

@@ -4,4 +4,5 @@
  *
  * @see example.inventory.InventoryInternal
  */
+@org.springframework.lang.NonNullApi
 package example.inventory;

spring-modulith-example/src/main/java/example/order/Order.java

@@ -15,18 +15,20 @@
  */
 package example.order;
 
+import example.order.Order.OrderIdentifier;
+import lombok.Getter;
+
 import java.util.UUID;
 
+import org.jmolecules.ddd.types.AggregateRoot;
+import org.jmolecules.ddd.types.Identifier;
+
 /**
  * @author Oliver Drotbohm
  */
-public class Order {
+public class Order implements AggregateRoot<Order, OrderIdentifier> {
 
-	private OrderIdentifier id = new OrderIdentifier(UUID.randomUUID());
+	private @Getter OrderIdentifier id = new OrderIdentifier(UUID.randomUUID());
 
-	public OrderIdentifier getId() {
-		return id;
-	}
-
-	public static record OrderIdentifier(UUID id) {}
+	public static record OrderIdentifier(UUID id) implements Identifier {}
 }

spring-modulith-example/src/main/java/example/order/OrderManagement.java

@@ -16,6 +16,8 @@
 package example.order;
 
 import example.order.internal.OrderInternal;
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
 
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.stereotype.Service;
@@ -25,16 +27,11 @@ import org.springframework.transaction.annotation.Transactional;
  * @author Oliver Drotbohm
  */
 @Service
+@RequiredArgsConstructor
 public class OrderManagement {
 
-	final ApplicationEventPublisher events;
-	final OrderInternal dependency;
-
-	OrderManagement(ApplicationEventPublisher events, OrderInternal dependency) {
-
-		this.events = events;
-		this.dependency = dependency;
-	}
+	private final @NonNull ApplicationEventPublisher events;
+	private final @NonNull OrderInternal dependency;
 
 	@Transactional
 	public void complete(Order order) {

spring-modulith-example/src/main/java/example/order/internal/OrderInternal.java

@@ -18,7 +18,8 @@ package example.order.internal;
 import org.springframework.stereotype.Component;
 
 /**
- * Some order-internal application component.
+ * Some order-internal application component. Referring to it from the inventory module would be captured by
+ * {@link example.ModularityTests}.
  *
  * @author Oliver Drotbohm
  */

spring-modulith-example/src/main/java/example/order/package-info.java

@@ -4,4 +4,5 @@
  *
  * @see example.ModularityTests
  */
+@org.springframework.lang.NonNullApi
 package example.order;