INT-2935: Improve AELMP performance

spring-integration-gemfire/src/main/java/org/springframework/integration/gemfire/inbound/SpelMessageProducerSupport.java → spring-integration-core/src/main/java/org/springframework/integration/endpoint/ExpressionMessageProducerSupport.java

@@ -1,38 +1,36 @@
 /*
- * Copyright 2002-2011 the original author or authors.
- * 
+ * Copyright 2002-2013 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.integration.gemfire.inbound;
+package org.springframework.integration.endpoint;
 
 import org.springframework.expression.Expression;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.integration.endpoint.MessageProducerSupport;
 
 /**
+ * A {@link MessageProducerSupport} sub-class that provides {@linkplain #payloadExpression}
+ * evaluation with result as a payload for Message to send.
+ *
  * @author David Turanski
+ * @author Artem Bilan
  * @since 2.1
  *
  */
-abstract class SpelMessageProducerSupport extends MessageProducerSupport {
-
-	private volatile Expression payloadExpression;
+public abstract class ExpressionMessageProducerSupport extends MessageProducerSupport {
 
 	private final SpelExpressionParser parser = new SpelExpressionParser();
 
-
-	@Override
-	protected void onInit(){
-		super.onInit();
-	}
-
+	private volatile Expression payloadExpression;
+
 	public void setPayloadExpression(String payloadExpression) {
 		if (payloadExpression == null) {
 			this.payloadExpression = null;
@@ -41,14 +39,13 @@ public void setPayloadExpression(String payloadExpression) {
 			this.payloadExpression = this.parser.parseExpression(payloadExpression);
 		}
 	}
-	
-	protected Object evaluationResult(Object payload){
+
+	protected Object evaluatePayloadExpression(Object payload){
 		Object evaluationResult = payload;
 		if (payloadExpression != null) {
 			evaluationResult = payloadExpression.getValue(payload);
 		}
 		return evaluationResult;
 	}
-
 
 }

spring-integration-event/src/main/java/org/springframework/integration/event/inbound/ApplicationEventListeningMessageProducer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2010 the original author or authors.
+ * Copyright 2002-2013 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.
@@ -16,85 +16,111 @@
 
 package org.springframework.integration.event.inbound;
 
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
-import java.util.concurrent.CopyOnWriteArraySet;
 
 import org.springframework.context.ApplicationEvent;
-import org.springframework.context.ApplicationListener;
 import org.springframework.context.event.ApplicationContextEvent;
-import org.springframework.expression.Expression;
-import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.context.event.ApplicationEventMulticaster;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.event.SmartApplicationListener;
+import org.springframework.context.support.AbstractApplicationContext;
+import org.springframework.core.Ordered;
 import org.springframework.integration.Message;
-import org.springframework.integration.endpoint.MessageProducerSupport;
+import org.springframework.integration.endpoint.ExpressionMessageProducerSupport;
 import org.springframework.integration.support.MessageBuilder;
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 
 /**
- * An inbound Channel Adapter that passes Spring {@link ApplicationEvent ApplicationEvents} within messages.
+ * An inbound Channel Adapter that implements {@link ApplicationListener} and
+ * passes Spring {@link ApplicationEvent ApplicationEvents} within messages.
  * If a {@link #setPayloadExpression(String) payloadExpression} is provided, it will be evaluated against
  * the ApplicationEvent instance to create the Message payload. Otherwise, the event itself will be the payload.
- * 
+ *
  * @author Mark Fisher
+ * @author Artem Bilan
+ * @see ApplicationEventMulticaster
+ * @see ExpressionMessageProducerSupport
  */
-public class ApplicationEventListeningMessageProducer extends MessageProducerSupport implements ApplicationListener<ApplicationEvent> {
+public class ApplicationEventListeningMessageProducer extends ExpressionMessageProducerSupport implements SmartApplicationListener {
 
-	private final Set<Class<? extends ApplicationEvent>> eventTypes = new CopyOnWriteArraySet<Class<? extends ApplicationEvent>>();
+	private volatile Set<Class<? extends ApplicationEvent>> eventTypes;
 
-	private volatile Expression payloadExpression;
+	private ApplicationEventMulticaster applicationEventMulticaster;
 
 	private volatile boolean active;
 
-	private final SpelExpressionParser parser = new SpelExpressionParser();
-
-
 	/**
 	 * Set the list of event types (classes that extend ApplicationEvent) that
 	 * this adapter should send to the message channel. By default, all event
 	 * types will be sent.
+	 * In additional this method re-register current instance as a {@link ApplicationListener}
+	 * in the {@link ApplicationEventMulticaster} to clear listeners cache and get a fresh cache entry
+	 * on next appropriate {@link ApplicationEvent}.
+	 *
+	 * @see ApplicationEventMulticaster#addApplicationListener
+	 * @see #supportsEventType
 	 */
 	@SuppressWarnings("unchecked")
-	public void setEventTypes(Class<? extends ApplicationEvent>[] eventTypes) {
-		Assert.notEmpty(eventTypes, "at least one event type is required");
-		synchronized (this.eventTypes) {
-			this.eventTypes.clear();
-			this.eventTypes.addAll(CollectionUtils.arrayToList(eventTypes));
-		}
-	}
+	public void setEventTypes(Class<? extends ApplicationEvent>... eventTypes) {
+		Set<Class<? extends ApplicationEvent>> eventSet = new HashSet<Class<? extends ApplicationEvent>>(CollectionUtils.arrayToList(eventTypes));
+		eventSet.remove(null);
+		this.eventTypes = (eventSet.size() > 0 ? eventSet : null);
 
-	/**
-	 * Provide an expression to be evaluated against the received ApplicationEvent
-	 * instance (the "root object") in order to create the Message payload. If none
-	 * is provided, the ApplicationEvent itself will be used as the payload.
-	 */
-	public void setPayloadExpression(String payloadExpression) {
-		if (payloadExpression == null) {
-			this.payloadExpression = null;
-		}
-		else {
-			this.payloadExpression = this.parser.parseExpression(payloadExpression);
+		if (this.applicationEventMulticaster != null) {
+			this.applicationEventMulticaster.addApplicationListener(this);
 		}
 	}
 
 	public String getComponentType() {
 		return "event:inbound-channel-adapter";
 	}
 
+	@Override
+	protected void onInit() {
+		super.onInit();
+		this.applicationEventMulticaster = this.getBeanFactory()
+				.getBean(AbstractApplicationContext.APPLICATION_EVENT_MULTICASTER_BEAN_NAME, ApplicationEventMulticaster.class);
+		Assert.notNull(this.applicationEventMulticaster,
+				"To use ApplicationListeners the 'applicationEventMulticaster' bean must be supplied within ApplicationContext.");
+	}
+
 	public void onApplicationEvent(ApplicationEvent event) {
 		if (this.active || event instanceof ApplicationContextEvent) {
-			if (CollectionUtils.isEmpty(this.eventTypes)) {
-				this.sendEventAsMessage(event);
-				return;
+			if (event.getSource() instanceof Message<?>) {
+				this.sendMessage((Message<?>) event.getSource());
 			}
-			for (Class<? extends ApplicationEvent> eventType : this.eventTypes) {
-				if (eventType.isAssignableFrom(event.getClass())) {
-					this.sendEventAsMessage(event);
-					return;
-				}
+			else {
+				Object payload = this.evaluatePayloadExpression(event);
+				this.sendMessage(MessageBuilder.withPayload(payload).build());
 			}
 		}
 	}
 
+	public boolean supportsEventType(Class<? extends ApplicationEvent> eventType) {
+		if (this.eventTypes == null) {
+			return true;
+		}
+		for (Class<? extends ApplicationEvent> type : this.eventTypes) {
+			if (type.isAssignableFrom(eventType)) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	public boolean supportsSourceType(Class<?> sourceType) {
+		return true;
+	}
+
+	public int getOrder() {
+		return Ordered.LOWEST_PRECEDENCE;
+	}
+
 	@Override
 	protected void doStart() {
 		this.active = true;
@@ -105,14 +131,5 @@ protected void doStop() {
 		this.active = false;
 	}
 
-	private void sendEventAsMessage(ApplicationEvent event) {
-		if (event.getSource() instanceof Message<?>) {
-			this.sendMessage((Message<?>) event.getSource());
-		}
-		else {
-			Object payload = (this.payloadExpression != null) ? this.payloadExpression.getValue(event) : event;
-			this.sendMessage(MessageBuilder.withPayload(payload).build());
-		}
-	}
-
 }
+

spring-integration-event/src/test/java/log4j.properties

@@ -2,7 +2,7 @@ log4j.rootCategory=WARN, stdout
 
 log4j.appender.stdout=org.apache.log4j.ConsoleAppender
 log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
-log4j.appender.stdout.layout.ConversionPattern=%c{1}: %m%n
+log4j.appender.stdout.layout.ConversionPattern=%c{1}: (%t) %m%n
 
 log4j.category.org.springframework.integration=WARN
-log4j.category.org.springframework.integration.file=WARN
+log4j.category.org.springframework.integration.event=INFO