DefaultSingletonBeanRegistry avoids singletonObjects lock wherever possible for non-singleton factory performance

Also fixing setCurrentlyInCreation to use a concurrent Set and to apply to prototype beans as well.

Issue: SPR-9819

Author: jhoeller

spring-beans/src/main/java/org/springframework/beans/factory/config/ConfigurableBeanFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2012 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.
@@ -321,8 +321,8 @@ public interface ConfigurableBeanFactory extends HierarchicalBeanFactory, Single
 	boolean isFactoryBean(String name) throws NoSuchBeanDefinitionException;
 
 	/**
-	 * Explicitly control in-creation status of the specified bean. For
-	 * container internal use only.
+	 * Explicitly control the current in-creation status of the specified bean.
+	 * For container-internal use only.
 	 * @param beanName the name of the bean
 	 * @param inCreation whether the bean is currently in creation
 	 * @since 3.1

spring-beans/src/main/java/org/springframework/beans/factory/support/AbstractBeanFactory.java

@@ -897,6 +897,22 @@ else if (containsSingleton(beanName)) {
 		return isFactoryBean(beanName, getMergedLocalBeanDefinition(beanName));
 	}
 
+	@Override
+	public boolean isActuallyInCreation(String beanName) {
+		return isSingletonCurrentlyInCreation(beanName) || isPrototypeCurrentlyInCreation(beanName);
+	}
+
+	/**
+	 * Return whether the specified prototype bean is currently in creation
+	 * (within the current thread).
+	 * @param beanName the name of the bean
+	 */
+	protected boolean isPrototypeCurrentlyInCreation(String beanName) {
+		Object curVal = this.prototypesCurrentlyInCreation.get();
+		return (curVal != null &&
+				(curVal.equals(beanName) || (curVal instanceof Set && ((Set<?>) curVal).contains(beanName))));
+	}
+
 	/**
 	 * Callback before prototype creation.
 	 * <p>The default implementation register the prototype as currently in creation.
@@ -942,22 +958,6 @@ else if (curVal instanceof Set) {
 		}
 	}
 
-	/**
-	 * Return whether the specified prototype bean is currently in creation
-	 * (within the current thread).
-	 * @param beanName the name of the bean
-	 */
-	protected final boolean isPrototypeCurrentlyInCreation(String beanName) {
-		Object curVal = this.prototypesCurrentlyInCreation.get();
-		return (curVal != null &&
-				(curVal.equals(beanName) || (curVal instanceof Set && ((Set<?>) curVal).contains(beanName))));
-	}
-
-	public boolean isCurrentlyInCreation(String beanName) {
-		Assert.notNull(beanName, "Bean name must not be null");
-		return isSingletonCurrentlyInCreation(beanName) || isPrototypeCurrentlyInCreation(beanName);
-	}
-
 	public void destroyBean(String beanName, Object beanInstance) {
 		destroyBean(beanName, beanInstance, getMergedLocalBeanDefinition(beanName));
 	}

spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java

@@ -16,9 +16,7 @@
 
 package org.springframework.beans.factory.support;
 
-import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
@@ -94,11 +92,11 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 	/** Set of registered singletons, containing the bean names in registration order */
 	private final Set<String> registeredSingletons = new LinkedHashSet<String>(16);
 
-	/** Names of beans that are currently in creation */
-	private final Set<String> singletonsCurrentlyInCreation = Collections.synchronizedSet(new HashSet<String>());
+	/** Names of beans that are currently in creation (using a ConcurrentHashMap as a Set) */
+	private final Map<String, Boolean> singletonsCurrentlyInCreation = new ConcurrentHashMap<String, Boolean>();
 
-	/** Names of beans currently excluded from in creation checks */
-	private final Set<String> inCreationCheckExclusions = new HashSet<String>();
+	/** Names of beans currently excluded from in creation checks (using a ConcurrentHashMap as a Set) */
+	private final Map<String, Boolean> inCreationCheckExclusions = new ConcurrentHashMap<String, Boolean>();
 
 	/** List of suppressed Exceptions, available for associating related causes */
 	private Set<Exception> suppressedExceptions;
@@ -166,7 +164,7 @@ protected void addSingletonFactory(String beanName, ObjectFactory singletonFacto
 	}
 
 	public Object getSingleton(String beanName) {
-		return getSingleton(beanName, isSingletonCurrentlyInCreation(beanName));
+		return getSingleton(beanName, true);
 	}
 
 	/**
@@ -179,10 +177,10 @@ public Object getSingleton(String beanName) {
 	 */
 	protected Object getSingleton(String beanName, boolean allowEarlyReference) {
 		Object singletonObject = this.singletonObjects.get(beanName);
-		if (singletonObject == null && allowEarlyReference) {
+		if (singletonObject == null && isSingletonCurrentlyInCreation(beanName)) {
 			synchronized (this.singletonObjects) {
 				singletonObject = this.earlySingletonObjects.get(beanName);
-				if (singletonObject == null) {
+				if (singletonObject == null && allowEarlyReference) {
 					ObjectFactory singletonFactory = this.singletonFactories.get(beanName);
 					if (singletonFactory != null) {
 						singletonObject = singletonFactory.getObject();
@@ -289,14 +287,43 @@ public int getSingletonCount() {
 	}
 
 
+	public void setCurrentlyInCreation(String beanName, boolean inCreation) {
+		Assert.notNull(beanName, "Bean name must not be null");
+		if (!inCreation) {
+			this.inCreationCheckExclusions.put(beanName, Boolean.TRUE);
+		}
+		else {
+			this.inCreationCheckExclusions.remove(beanName);
+		}
+	}
+
+	public boolean isCurrentlyInCreation(String beanName) {
+		Assert.notNull(beanName, "Bean name must not be null");
+		return (!this.inCreationCheckExclusions.containsKey(beanName) && isActuallyInCreation(beanName));
+	}
+
+	protected boolean isActuallyInCreation(String beanName) {
+		return isSingletonCurrentlyInCreation(beanName);
+	}
+
+	/**
+	 * Return whether the specified singleton bean is currently in creation
+	 * (within the entire factory).
+	 * @param beanName the name of the bean
+	 */
+	public boolean isSingletonCurrentlyInCreation(String beanName) {
+		return this.singletonsCurrentlyInCreation.containsKey(beanName);
+	}
+
 	/**
 	 * Callback before singleton creation.
 	 * <p>Default implementation register the singleton as currently in creation.
 	 * @param beanName the name of the singleton about to be created
 	 * @see #isSingletonCurrentlyInCreation
 	 */
 	protected void beforeSingletonCreation(String beanName) {
-		if (!this.inCreationCheckExclusions.contains(beanName) && !this.singletonsCurrentlyInCreation.add(beanName)) {
+		if (!this.inCreationCheckExclusions.containsKey(beanName) &&
+				this.singletonsCurrentlyInCreation.put(beanName, Boolean.TRUE) != null) {
 			throw new BeanCurrentlyInCreationException(beanName);
 		}
 	}
@@ -308,29 +335,12 @@ protected void beforeSingletonCreation(String beanName) {
 	 * @see #isSingletonCurrentlyInCreation
 	 */
 	protected void afterSingletonCreation(String beanName) {
-		if (!this.inCreationCheckExclusions.contains(beanName) && !this.singletonsCurrentlyInCreation.remove(beanName)) {
+		if (!this.inCreationCheckExclusions.containsKey(beanName) &&
+				!this.singletonsCurrentlyInCreation.remove(beanName)) {
 			throw new IllegalStateException("Singleton '" + beanName + "' isn't currently in creation");
 		}
 	}
 
-	public final void setCurrentlyInCreation(String beanName, boolean inCreation) {
-		if (!inCreation) {
-			this.inCreationCheckExclusions.add(beanName);
-		}
-		else {
-			this.inCreationCheckExclusions.remove(beanName);
-		}
-	}
-
-	/**
-	 * Return whether the specified singleton bean is currently in creation
-	 * (within the entire factory).
-	 * @param beanName the name of the bean
-	 */
-	public final boolean isSingletonCurrentlyInCreation(String beanName) {
-		return this.singletonsCurrentlyInCreation.contains(beanName);
-	}
-
 
 	/**
 	 * Add the given bean to the list of disposable beans in this registry.

spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java

@@ -56,7 +56,6 @@ class ConfigurationClassEnhancer {
 		DisposableBeanMethodInterceptor.class, NoOp.class };
 
 	private static final CallbackFilter CALLBACK_FILTER = new CallbackFilter() {
-
 		public int accept(Method candidateMethod) {
 			// Set up the callback filter to return the index of the BeanMethodInterceptor when
 			// handling a @Bean-annotated method; otherwise, return index of the NoOp callback.
@@ -72,7 +71,6 @@ public int accept(Method candidateMethod) {
 
 	private static final Callback DISPOSABLE_BEAN_METHOD_INTERCEPTOR = new DisposableBeanMethodInterceptor();
 
-
 	private final Callback[] callbackInstances;
 
 
@@ -162,6 +160,7 @@ private Class<?> createClass(Enhancer enhancer) {
 	private static class GetObjectMethodInterceptor implements MethodInterceptor {
 
 		private final ConfigurableBeanFactory beanFactory;
+
 		private final String beanName;
 
 		public GetObjectMethodInterceptor(ConfigurableBeanFactory beanFactory, String beanName) {
@@ -296,7 +295,8 @@ public Object intercept(Object enhancedConfigInstance, Method beanMethod, Object
 						this.beanFactory.setCurrentlyInCreation(beanName, false);
 					}
 					return this.beanFactory.getBean(beanName);
-				} finally {
+				}
+				finally {
 					if (alreadyInCreation) {
 						this.beanFactory.setCurrentlyInCreation(beanName, true);
 					}
@@ -347,6 +347,6 @@ private Object enhanceFactoryBean(Class<?> fbClass, String beanName) throws Inst
 			Enhancer.registerCallbacks(fbSubclass, callbackInstances);
 			return fbSubclass.newInstance();
 		}
-
 	}
+
 }