DATACMNS-209 - MappingContextEvent now carries its emitting MappingContext.

MappingContextEvent now has an wasEmittedBy(MappingContext<?, ?> context) method to allow identifying whether the event was emitted by the given MappingContext. Useful if multiple MappingContexts are in place and one wants to react on the events emitted by a particular one only.

spring-data-commons-core/src/main/java/org/springframework/data/mapping/context/AbstractMappingContext.java

@@ -296,7 +296,7 @@ public abstract class AbstractMappingContext<E extends MutablePersistentEntity<?
 
 			// Inform listeners
 			if (null != applicationEventPublisher) {
-				applicationEventPublisher.publishEvent(new MappingContextEvent<E, P>(entity));
+				applicationEventPublisher.publishEvent(new MappingContextEvent<E, P>(this, entity));
 			}
 
 			return entity;

spring-data-commons-core/src/main/java/org/springframework/data/mapping/event/MappingContextEvent.java

@@ -18,6 +18,7 @@ package org.springframework.data.mapping.event;
 import org.springframework.context.ApplicationEvent;
 import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.PersistentProperty;
+import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.util.Assert;
 
 /**
@@ -33,19 +34,24 @@ public class MappingContextEvent<E extends PersistentEntity<?, P>, P extends Per
 
 	private static final long serialVersionUID = 1336466833846092490L;
 
-	private final E source;
+	private final MappingContext<?, ?> source;
+	private final E entity;
 
 	/**
-	 * Creates a new {@link MappingContextEvent} for the given {@link PersistentEntity}.
+	 * Creates a new {@link MappingContextEvent} for the given {@link MappingContext} and {@link PersistentEntity}.
 	 * 
 	 * @param source must not be {@literal null}.
+	 * @param entity must not be {@literal null}.
 	 */
-	public MappingContextEvent(E source) {
+	public MappingContextEvent(MappingContext<?, ?> source, E entity) {
 
 		super(source);
 
 		Assert.notNull(source);
+		Assert.notNull(entity);
+
 		this.source = source;
+		this.entity = entity;
 	}
 
 	/**
@@ -54,6 +60,16 @@ public class MappingContextEvent<E extends PersistentEntity<?, P>, P extends Per
 	 * @return
 	 */
 	public E getPersistentEntity() {
-		return source;
+		return entity;
+	}
+
+	/**
+	 * Returns whether the {@link MappingContextEvent} was triggered by the given {@link MappingContext}.
+	 * 
+	 * @param context the {@link MappingContext} that potentially created the event.
+	 * @return
+	 */
+	public boolean wasEmittedBy(MappingContext<?, ?> context) {
+		return this.source.equals(context);
 	}
 }

spring-data-commons-core/src/test/java/org/springframework/data/mapping/event/MappingContextEventUnitTests.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2012 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mapping.event;
+
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.runners.MockitoJUnitRunner;
+import org.springframework.data.mapping.PersistentEntity;
+import org.springframework.data.mapping.PersistentProperty;
+import org.springframework.data.mapping.context.MappingContext;
+
+/**
+ * Unit tests for {@link MappingContextEvent}.
+ * 
+ * @author Oliver Gierke
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class MappingContextEventUnitTests<E extends PersistentEntity<?, P>, P extends PersistentProperty<P>> {
+
+	@Mock
+	E entity;
+
+	@Mock
+	MappingContext<?, ?> mappingContext, otherMappingContext;
+
+	@Test
+	public void returnsPersistentEntityHandedToTheEvent() {
+
+		MappingContextEvent<E, P> event = new MappingContextEvent<E, P>(mappingContext, entity);
+		assertThat(event.getPersistentEntity(), is(entity));
+	}
+
+	@Test
+	public void usesMappingContextAsEventSource() {
+
+		MappingContextEvent<E, P> event = new MappingContextEvent<E, P>(mappingContext, entity);
+		assertThat(event.getSource(), is((Object) mappingContext));
+	}
+
+	@Test
+	public void detectsEmittingMappingContextCorrectly() {
+
+		MappingContextEvent<E, P> event = new MappingContextEvent<E, P>(mappingContext, entity);
+		assertThat(event.wasEmittedBy(mappingContext), is(true));
+		assertThat(event.wasEmittedBy(otherMappingContext), is(false));
+	}
+}