Allow disabling entity lifecycle events.

We now support disabling lifecycle events through the Template API to reduce the framework overhead when events are not needed.

Closes #1291

Author: mp911de

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/JdbcAggregateTemplate.java

@@ -34,6 +34,7 @@
 import org.springframework.data.jdbc.core.convert.JdbcConverter;
 import org.springframework.data.mapping.IdentifierAccessor;
 import org.springframework.data.mapping.callback.EntityCallbacks;
+import org.springframework.data.relational.core.EntityLifecycleEventDelegate;
 import org.springframework.data.relational.core.conversion.AggregateChange;
 import org.springframework.data.relational.core.conversion.BatchingAggregateChange;
 import org.springframework.data.relational.core.conversion.DeleteAggregateChange;
@@ -67,7 +68,7 @@
  */
 public class JdbcAggregateTemplate implements JdbcAggregateOperations {
 
-	private final ApplicationEventPublisher publisher;
+	private final EntityLifecycleEventDelegate eventDelegate = new EntityLifecycleEventDelegate();
 	private final RelationalMappingContext context;
 
 	private final RelationalEntityDeleteWriter jdbcEntityDeleteWriter;
@@ -95,7 +96,7 @@ public JdbcAggregateTemplate(ApplicationContext publisher, RelationalMappingCont
 		Assert.notNull(converter, "RelationalConverter must not be null");
 		Assert.notNull(dataAccessStrategy, "DataAccessStrategy must not be null");
 
-		this.publisher = publisher;
+		this.eventDelegate.setPublisher(publisher);
 		this.context = context;
 		this.accessStrategy = dataAccessStrategy;
 		this.converter = converter;
@@ -123,7 +124,7 @@ public JdbcAggregateTemplate(ApplicationEventPublisher publisher, RelationalMapp
 		Assert.notNull(converter, "RelationalConverter must not be null");
 		Assert.notNull(dataAccessStrategy, "DataAccessStrategy must not be null");
 
-		this.publisher = publisher;
+		this.eventDelegate.setPublisher(publisher);
 		this.context = context;
 		this.accessStrategy = dataAccessStrategy;
 		this.converter = converter;
@@ -145,6 +146,18 @@ public void setEntityCallbacks(EntityCallbacks entityCallbacks) {
 		this.entityCallbacks = entityCallbacks;
 	}
 
+	/**
+	 * Configure whether lifecycle events such as {@link AfterSaveEvent}, {@link BeforeSaveEvent}, etc. should be
+	 * published or whether emission should be suppressed. Enabled by default.
+	 *
+	 * @param enabled {@code true} to enable entity lifecycle events; {@code false} to disable entity lifecycle events.
+	 * @since 3.0
+	 * @see AbstractRelationalEvent
+	 */
+	public void setEntityLifecycleEventsEnabled(boolean enabled) {
+		this.eventDelegate.setEventsEnabled(enabled);
+	}
+
 	@Override
 	public <T> T save(T instance) {
 
@@ -529,34 +542,32 @@ private <T> Iterable<T> triggerAfterConvert(Iterable<T> all) {
 
 	private <T> T triggerAfterConvert(T entity) {
 
-		publisher.publishEvent(new AfterConvertEvent<>(entity));
+		eventDelegate.publishEvent(() -> new AfterConvertEvent<>(entity));
 		return entityCallbacks.callback(AfterConvertCallback.class, entity);
 	}
 
 	private <T> T triggerBeforeConvert(T aggregateRoot) {
 
-		publisher.publishEvent(new BeforeConvertEvent<>(aggregateRoot));
-
+		eventDelegate.publishEvent(() -> new BeforeConvertEvent<>(aggregateRoot));
 		return entityCallbacks.callback(BeforeConvertCallback.class, aggregateRoot);
 	}
 
 	private <T> T triggerBeforeSave(T aggregateRoot, AggregateChange<T> change) {
 
-		publisher.publishEvent(new BeforeSaveEvent<>(aggregateRoot, change));
+		eventDelegate.publishEvent(() -> new BeforeSaveEvent<>(aggregateRoot, change));
 
 		return entityCallbacks.callback(BeforeSaveCallback.class, aggregateRoot, change);
 	}
 
 	private <T> T triggerAfterSave(T aggregateRoot, AggregateChange<T> change) {
 
-		publisher.publishEvent(new AfterSaveEvent<>(aggregateRoot, change));
-
+		eventDelegate.publishEvent(() -> new AfterSaveEvent<>(aggregateRoot, change));
 		return entityCallbacks.callback(AfterSaveCallback.class, aggregateRoot);
 	}
 
 	private <T> void triggerAfterDelete(@Nullable T aggregateRoot, Object id, AggregateChange<T> change) {
 
-		publisher.publishEvent(new AfterDeleteEvent<>(Identifier.of(id), aggregateRoot, change));
+		eventDelegate.publishEvent(() -> new AfterDeleteEvent<>(Identifier.of(id), aggregateRoot, change));
 
 		if (aggregateRoot != null) {
 			entityCallbacks.callback(AfterDeleteCallback.class, aggregateRoot);
@@ -566,7 +577,7 @@ private <T> void triggerAfterDelete(@Nullable T aggregateRoot, Object id, Aggreg
 	@Nullable
 	private <T> T triggerBeforeDelete(@Nullable T aggregateRoot, Object id, MutableAggregateChange<T> change) {
 
-		publisher.publishEvent(new BeforeDeleteEvent<>(Identifier.of(id), aggregateRoot, change));
+		eventDelegate.publishEvent(() -> new BeforeDeleteEvent<>(Identifier.of(id), aggregateRoot, change));
 
 		if (aggregateRoot != null) {
 			return entityCallbacks.callback(BeforeDeleteCallback.class, aggregateRoot, change);

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/core/JdbcAggregateTemplateUnitTests.java

@@ -30,6 +30,7 @@
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
+
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.data.annotation.Id;
 import org.springframework.data.annotation.Version;
@@ -62,7 +63,7 @@
 @ExtendWith(MockitoExtension.class)
 public class JdbcAggregateTemplateUnitTests {
 
-	JdbcAggregateOperations template;
+	JdbcAggregateTemplate template;
 
 	@Mock DataAccessStrategy dataAccessStrategy;
 	@Mock ApplicationEventPublisher eventPublisher;
@@ -97,7 +98,7 @@ public void findAllByIdWithEmptyListMustReturnEmptyResult() {
 		assertThat(template.findAllById(emptyList(), SampleEntity.class)).isEmpty();
 	}
 
-	@Test // DATAJDBC-393
+	@Test // DATAJDBC-393, GH-1291
 	public void callbackOnSave() {
 
 		SampleEntity first = new SampleEntity(null, "Alfred");
@@ -112,6 +113,22 @@ public void callbackOnSave() {
 		verify(callbacks).callback(eq(BeforeSaveCallback.class), eq(second), any(MutableAggregateChange.class));
 		verify(callbacks).callback(AfterSaveCallback.class, third);
 		assertThat(last).isEqualTo(third);
+		verify(eventPublisher, times(3)).publishEvent(any(Object.class));
+	}
+
+	@Test // GH-1291
+	public void doesNotEmitEvents() {
+
+		SampleEntity first = new SampleEntity(null, "Alfred");
+		SampleEntity second = new SampleEntity(23L, "Alfred E.");
+		SampleEntity third = new SampleEntity(23L, "Neumann");
+
+		when(callbacks.callback(any(Class.class), any(), any())).thenReturn(second, third);
+
+		template.setEntityLifecycleEventsEnabled(false);
+		template.save(first);
+
+		verifyNoInteractions(eventPublisher);
 	}
 
 	@Test // GH-1137

spring-data-relational/src/main/java/org/springframework/data/relational/core/EntityLifecycleEventDelegate.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 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
+ *
+ *      https://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.relational.core;
+
+import java.util.function.Supplier;
+
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.lang.Nullable;
+
+/**
+ * Delegate class to encapsulate lifecycle event configuration and publishing. Event creation is deferred within an
+ * event {@link Supplier} to delay the actual event object creation.
+ *
+ * @author Mark Paluch
+ * @since 3.0
+ * @see ApplicationEventPublisher
+ */
+public class EntityLifecycleEventDelegate {
+
+	private @Nullable ApplicationEventPublisher publisher;
+	private boolean eventsEnabled = true;
+
+	public void setPublisher(@Nullable ApplicationEventPublisher publisher) {
+		this.publisher = publisher;
+	}
+
+	public boolean isEventsEnabled() {
+		return eventsEnabled;
+	}
+
+	public void setEventsEnabled(boolean eventsEnabled) {
+		this.eventsEnabled = eventsEnabled;
+	}
+
+	/**
+	 * Publish an application event if event publishing is enabled.
+	 *
+	 * @param eventSupplier the supplier for application events.
+	 */
+	public void publishEvent(Supplier<?> eventSupplier) {
+
+		if (canPublishEvent()) {
+			publisher.publishEvent(eventSupplier.get());
+		}
+	}
+
+	private boolean canPublishEvent() {
+		return publisher != null && eventsEnabled;
+	}
+}

src/main/asciidoc/jdbc.adoc

@@ -829,6 +829,10 @@ Note that the type used for prefixing the statement name is the name of the aggr
 == Lifecycle Events
 
 Spring Data JDBC triggers events that get published to any matching `ApplicationListener` beans in the application context.
+
+Entity lifecycle events can be costly and you may notice a change in the performance profile when loading large result sets.
+You can disable lifecycle events on the link:{javadoc-base}org/springframework/data/jdbc/core/JdbcAggregateTemplate.html#setEntityLifecycleEventsEnabled(boolean)[Template API].
+
 For example, the following listener gets invoked before an aggregate gets saved:
 
 ====
@@ -1100,4 +1104,4 @@ Select * from user u where u.lastname = lastname LOCK IN SHARE MODE
 ----
 ====
 
-Alternative to `LockMode.PESSIMISTIC_READ` you can use `LockMode.PESSIMISTIC_WRITE`.
+Alternative to `LockMode.PESSIMISTIC_READ` you can use `LockMode.PESSIMISTIC_WRITE`.