BAEL-2435 Minor clean ups

-Add toString() function to messages/query-model
-Fix typo in exception
-Reorder event handlers in OrderedProductsEventHandler
-Replace usage of constants for local fields
-Add missing Aggregate test case

axon/src/main/java/com/baeldung/axon/commandmodel/OrderAggregate.java

@@ -34,7 +34,7 @@ public class OrderAggregate {
     @CommandHandler
     public void handle(ShipOrderCommand command) {
         if (!orderConfirmed) {
-            throw new IllegalStateException("Cannot ship an order which has not ben confirmed yet.");
+            throw new IllegalStateException("Cannot ship an order which has not been confirmed yet.");
         }
 
         apply(new OrderShippedEvent(orderId));

axon/src/main/java/com/baeldung/axon/coreapi/commands/ConfirmOrderCommand.java

@@ -33,4 +33,11 @@ public class ConfirmOrderCommand {
         final ConfirmOrderCommand other = (ConfirmOrderCommand) obj;
         return Objects.equals(this.orderId, other.orderId);
     }
+
+    @Override
+    public String toString() {
+        return "ConfirmOrderCommand{" +
+                "orderId='" + orderId + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/commands/PlaceOrderCommand.java

@@ -40,4 +40,12 @@ public class PlaceOrderCommand {
         return Objects.equals(this.orderId, other.orderId)
                 && Objects.equals(this.product, other.product);
     }
+
+    @Override
+    public String toString() {
+        return "PlaceOrderCommand{" +
+                "orderId='" + orderId + '\'' +
+                ", product='" + product + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/commands/ShipOrderCommand.java

@@ -33,4 +33,11 @@ public class ShipOrderCommand {
         final ShipOrderCommand other = (ShipOrderCommand) obj;
         return Objects.equals(this.orderId, other.orderId);
     }
+
+    @Override
+    public String toString() {
+        return "ShipOrderCommand{" +
+                "orderId='" + orderId + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/events/OrderConfirmedEvent.java

@@ -30,4 +30,11 @@ public class OrderConfirmedEvent {
         final OrderConfirmedEvent other = (OrderConfirmedEvent) obj;
         return Objects.equals(this.orderId, other.orderId);
     }
+
+    @Override
+    public String toString() {
+        return "OrderConfirmedEvent{" +
+                "orderId='" + orderId + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/events/OrderPlacedEvent.java

@@ -37,4 +37,12 @@ public class OrderPlacedEvent {
         return Objects.equals(this.orderId, other.orderId)
                 && Objects.equals(this.product, other.product);
     }
+
+    @Override
+    public String toString() {
+        return "OrderPlacedEvent{" +
+                "orderId='" + orderId + '\'' +
+                ", product='" + product + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/events/OrderShippedEvent.java

@@ -30,4 +30,11 @@ public class OrderShippedEvent {
         final OrderShippedEvent other = (OrderShippedEvent) obj;
         return Objects.equals(this.orderId, other.orderId);
     }
+
+    @Override
+    public String toString() {
+        return "OrderShippedEvent{" +
+                "orderId='" + orderId + '\'' +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/coreapi/queries/OrderedProduct.java

@@ -52,4 +52,13 @@ public class OrderedProduct {
                 && Objects.equals(this.product, other.product)
                 && Objects.equals(this.orderStatus, other.orderStatus);
     }
+
+    @Override
+    public String toString() {
+        return "OrderedProduct{" +
+                "orderId='" + orderId + '\'' +
+                ", product='" + product + '\'' +
+                ", orderStatus=" + orderStatus +
+                '}';
+    }
 }

axon/src/main/java/com/baeldung/axon/gui/OrderRestEndpoint.java

@@ -19,8 +19,6 @@ import com.baeldung.axon.coreapi.queries.OrderedProduct;
 @RestController
 public class OrderRestEndpoint {
 
-    private static final String DEFAULT_PRODUCT = "Deluxe Chair";
-
     private final CommandGateway commandGateway;
     private final QueryGateway queryGateway;
 
@@ -32,7 +30,7 @@ public class OrderRestEndpoint {
     @PostMapping("/ship-order")
     public void shipOrder() {
         String orderId = UUID.randomUUID().toString();
-        commandGateway.send(new PlaceOrderCommand(orderId, DEFAULT_PRODUCT));
+        commandGateway.send(new PlaceOrderCommand(orderId, "Deluxe Chair"));
         commandGateway.send(new ConfirmOrderCommand(orderId));
         commandGateway.send(new ShipOrderCommand(orderId));
     }
@@ -40,7 +38,7 @@ public class OrderRestEndpoint {
     @PostMapping("/ship-unconfirmed-order")
     public void shipUnconfirmedOrder() {
         String orderId = UUID.randomUUID().toString();
-        commandGateway.send(new PlaceOrderCommand(orderId, DEFAULT_PRODUCT));
+        commandGateway.send(new PlaceOrderCommand(orderId, "Deluxe Chair"));
         // This throws an exception, as an Order cannot be shipped if it has not been confirmed yet.
         commandGateway.send(new ShipOrderCommand(orderId));
     }

axon/src/main/java/com/baeldung/axon/querymodel/OrderedProductsEventHandler.java

@@ -24,15 +24,6 @@ public class OrderedProductsEventHandler {
     public void on(OrderPlacedEvent event) {
         String orderId = event.getOrderId();
         orderedProducts.put(orderId, new OrderedProduct(orderId, event.getProduct()));
-
-    }
-
-    @EventHandler
-    public void on(OrderShippedEvent event) {
-        orderedProducts.computeIfPresent(event.getOrderId(), (orderId, orderedProduct) -> {
-            orderedProduct.setOrderShipped();
-            return orderedProduct;
-        });
     }
 
     @EventHandler
@@ -43,6 +34,14 @@ public class OrderedProductsEventHandler {
         });
     }
 
+    @EventHandler
+    public void on(OrderShippedEvent event) {
+        orderedProducts.computeIfPresent(event.getOrderId(), (orderId, orderedProduct) -> {
+            orderedProduct.setOrderShipped();
+            return orderedProduct;
+        });
+    }
+
     @QueryHandler
     public List<OrderedProduct> handle(FindAllOrderedProductsQuery query) {
         return new ArrayList<>(orderedProducts.values());

axon/src/test/java/com/baeldung/axon/commandmodel/OrderAggregateUnitTest.java

@@ -6,6 +6,7 @@ import org.axonframework.test.aggregate.AggregateTestFixture;
 import org.axonframework.test.aggregate.FixtureConfiguration;
 import org.junit.*;
 
+import com.baeldung.axon.coreapi.commands.ConfirmOrderCommand;
 import com.baeldung.axon.coreapi.commands.PlaceOrderCommand;
 import com.baeldung.axon.coreapi.commands.ShipOrderCommand;
 import com.baeldung.axon.coreapi.events.OrderConfirmedEvent;
@@ -14,9 +15,6 @@ import com.baeldung.axon.coreapi.events.OrderShippedEvent;
 
 public class OrderAggregateUnitTest {
 
-    private static final String ORDER_ID = UUID.randomUUID().toString();
-    private static final String DEFAULT_PRODUCT = "Deluxe Chair";
-
     private FixtureConfiguration<OrderAggregate> fixture;
 
     @Before
@@ -26,23 +24,38 @@ public class OrderAggregateUnitTest {
 
     @Test
     public void giveNoPriorActivity_whenPlaceOrderCommand_thenShouldPublishOrderPlacedEvent() {
+        String orderId = UUID.randomUUID().toString();
+        String product = "Deluxe Chair";
         fixture.givenNoPriorActivity()
-               .when(new PlaceOrderCommand(ORDER_ID, DEFAULT_PRODUCT))
+               .when(new PlaceOrderCommand(orderId, product))
-               .expectEvents(new OrderPlacedEvent(ORDER_ID, DEFAULT_PRODUCT));
+               .expectEvents(new OrderPlacedEvent(orderId, product));
+    }
+
+    @Test
+    public void givenOrderPlacedEvent_whenConfirmOrderCommand_thenShouldPublishOrderConfirmedEvent() {
+        String orderId = UUID.randomUUID().toString();
+        String product = "Deluxe Chair";
+        fixture.given(new OrderPlacedEvent(orderId, product))
+               .when(new ConfirmOrderCommand(orderId))
+               .expectEvents(new OrderConfirmedEvent(orderId));
     }
 
     @Test
     public void givenOrderPlacedEvent_whenShipOrderCommand_thenShouldThrowIllegalStateException() {
-        fixture.given(new OrderPlacedEvent(ORDER_ID, DEFAULT_PRODUCT))
+        String orderId = UUID.randomUUID().toString();
-               .when(new ShipOrderCommand(ORDER_ID))
+        String product = "Deluxe Chair";
+        fixture.given(new OrderPlacedEvent(orderId, product))
+               .when(new ShipOrderCommand(orderId))
                .expectException(IllegalStateException.class);
     }
 
     @Test
     public void givenOrderPlacedEventAndOrderConfirmedEvent_whenShipOrderCommand_thenShouldPublishOrderShippedEvent() {
-        fixture.given(new OrderPlacedEvent(ORDER_ID, DEFAULT_PRODUCT), new OrderConfirmedEvent(ORDER_ID))
+        String orderId = UUID.randomUUID().toString();
-               .when(new ShipOrderCommand(ORDER_ID))
+        String product = "Deluxe Chair";
-               .expectEvents(new OrderShippedEvent(ORDER_ID));
+        fixture.given(new OrderPlacedEvent(orderId, product), new OrderConfirmedEvent(orderId))
+               .when(new ShipOrderCommand(orderId))
+               .expectEvents(new OrderShippedEvent(orderId));
     }
 
 }