BeanFactoryAnnotationUtils provides qualifiedBeansOfType method

Includes consistent upfront resolution of factory method annotations.

Issue: SPR-8891

Author: jhoeller

spring-beans/src/main/java/org/springframework/beans/factory/annotation/BeanFactoryAnnotationUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -17,16 +17,18 @@
 package org.springframework.beans.factory.annotation;
 
 import java.lang.reflect.Method;
+import java.util.LinkedHashMap;
+import java.util.Map;
 import java.util.function.Predicate;
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryUtils;
+import org.springframework.beans.factory.ListableBeanFactory;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableBeanFactory;
-import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.beans.factory.support.AutowireCandidateQualifier;
 import org.springframework.beans.factory.support.RootBeanDefinition;
@@ -35,8 +37,8 @@
 import org.springframework.util.Assert;
 
 /**
- * Convenience methods performing bean lookups related to annotations, for example
- * Spring's {@link Qualifier @Qualifier} annotation.
+ * Convenience methods performing bean lookups related to Spring-specific annotations,
+ * for example Spring's {@link Qualifier @Qualifier} annotation.
  *
  * @author Juergen Hoeller
  * @author Chris Beams
@@ -45,27 +47,52 @@
  */
 public abstract class BeanFactoryAnnotationUtils {
 
+	/**
+	 * Retrieve all bean of type {@code T} from the given {@code BeanFactory} declaring a
+	 * qualifier (e.g. via {@code <qualifier>} or {@code @Qualifier}) matching the given
+	 * qualifier, or having a bean name matching the given qualifier.
+	 * @param beanFactory the factory to get the target beans from (also searching ancestors)
+	 * @param beanType the type of beans to retrieve
+	 * @param qualifier the qualifier for selecting among all type matches
+	 * @return the matching beans of type {@code T}
+	 * @throws BeansException if any of the matching beans could not be created
+	 * @since 5.1.1
+	 * @see BeanFactoryUtils#beansOfTypeIncludingAncestors(ListableBeanFactory, Class)
+	 */
+	public static <T> Map<String, T> qualifiedBeansOfType(
+			ListableBeanFactory beanFactory, Class<T> beanType, String qualifier) throws BeansException {
+
+		String[] candidateBeans = BeanFactoryUtils.beanNamesForTypeIncludingAncestors(beanFactory, beanType);
+		Map<String, T> result = new LinkedHashMap<>(4);
+		for (String beanName : candidateBeans) {
+			if (isQualifierMatch(qualifier::equals, beanName, beanFactory)) {
+				result.put(beanName, beanFactory.getBean(beanName, beanType));
+			}
+		}
+		return result;
+	}
+
 	/**
 	 * Obtain a bean of type {@code T} from the given {@code BeanFactory} declaring a
 	 * qualifier (e.g. via {@code <qualifier>} or {@code @Qualifier}) matching the given
 	 * qualifier, or having a bean name matching the given qualifier.
-	 * @param beanFactory the BeanFactory to get the target bean from
+	 * @param beanFactory the factory to get the target bean from (also searching ancestors)
 	 * @param beanType the type of bean to retrieve
 	 * @param qualifier the qualifier for selecting between multiple bean matches
 	 * @return the matching bean of type {@code T} (never {@code null})
 	 * @throws NoUniqueBeanDefinitionException if multiple matching beans of type {@code T} found
 	 * @throws NoSuchBeanDefinitionException if no matching bean of type {@code T} found
 	 * @throws BeansException if the bean could not be created
-	 * @see BeanFactory#getBean(Class)
+	 * @see BeanFactoryUtils#beanOfTypeIncludingAncestors(ListableBeanFactory, Class)
 	 */
 	public static <T> T qualifiedBeanOfType(BeanFactory beanFactory, Class<T> beanType, String qualifier)
 			throws BeansException {
 
 		Assert.notNull(beanFactory, "BeanFactory must not be null");
 
-		if (beanFactory instanceof ConfigurableListableBeanFactory) {
+		if (beanFactory instanceof ListableBeanFactory) {
 			// Full qualifier matching supported.
-			return qualifiedBeanOfType((ConfigurableListableBeanFactory) beanFactory, beanType, qualifier);
+			return qualifiedBeanOfType((ListableBeanFactory) beanFactory, beanType, qualifier);
 		}
 		else if (beanFactory.containsBean(qualifier)) {
 			// Fallback: target bean at least found by bean name.
@@ -82,12 +109,12 @@ else if (beanFactory.containsBean(qualifier)) {
 	/**
 	 * Obtain a bean of type {@code T} from the given {@code BeanFactory} declaring a qualifier
 	 * (e.g. {@code <qualifier>} or {@code @Qualifier}) matching the given qualifier).
-	 * @param bf the BeanFactory to get the target bean from
+	 * @param bf the factory to get the target bean from
 	 * @param beanType the type of bean to retrieve
 	 * @param qualifier the qualifier for selecting between multiple bean matches
 	 * @return the matching bean of type {@code T} (never {@code null})
 	 */
-	private static <T> T qualifiedBeanOfType(ConfigurableListableBeanFactory bf, Class<T> beanType, String qualifier) {
+	private static <T> T qualifiedBeanOfType(ListableBeanFactory bf, Class<T> beanType, String qualifier) {
 		String[] candidateBeans = BeanFactoryUtils.beanNamesForTypeIncludingAncestors(bf, beanType);
 		String matchingBean = null;
 		for (String beanName : candidateBeans) {
@@ -115,14 +142,14 @@ else if (bf.containsBean(qualifier)) {
 	 * Check whether the named bean declares a qualifier of the given name.
 	 * @param qualifier the qualifier to match
 	 * @param beanName the name of the candidate bean
-	 * @param beanFactory the {@code BeanFactory} from which to retrieve the named bean
+	 * @param beanFactory the factory from which to retrieve the named bean
 	 * @return {@code true} if either the bean definition (in the XML case)
 	 * or the bean's factory method (in the {@code @Bean} case) defines a matching
 	 * qualifier value (through {@code <qualifier>} or {@code @Qualifier})
 	 * @since 5.0
 	 */
-	public static boolean isQualifierMatch(Predicate<String> qualifier, String beanName,
-			@Nullable BeanFactory beanFactory) {
+	public static boolean isQualifierMatch(
+			Predicate<String> qualifier, String beanName, @Nullable BeanFactory beanFactory) {
 
 		// Try quick bean name or alias match first...
 		if (qualifier.test(beanName)) {
@@ -135,6 +162,7 @@ public static boolean isQualifierMatch(Predicate<String> qualifier, String beanN
 				}
 			}
 			try {
+				Class<?> beanType = beanFactory.getType(beanName);
 				if (beanFactory instanceof ConfigurableBeanFactory) {
 					BeanDefinition bd = ((ConfigurableBeanFactory) beanFactory).getMergedBeanDefinition(beanName);
 					// Explicit qualifier metadata on bean definition? (typically in XML definition)
@@ -160,7 +188,6 @@ public static boolean isQualifierMatch(Predicate<String> qualifier, String beanN
 					}
 				}
 				// Corresponding qualifier on bean implementation class? (for custom user types)
-				Class<?> beanType = beanFactory.getType(beanName);
 				if (beanType != null) {
 					Qualifier targetAnnotation = AnnotationUtils.getAnnotation(beanType, Qualifier.class);
 					if (targetAnnotation != null) {

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

@@ -775,6 +775,11 @@ protected Class<?> getTypeForFactoryMethod(String beanName, RootBeanDefinition m
 			}
 		}
 
+		if (uniqueCandidate != null) {
+			synchronized (mbd.constructorArgumentLock) {
+				mbd.resolvedConstructorOrFactoryMethod = uniqueCandidate;
+			}
+		}
 		if (commonType == null) {
 			return null;
 		}

spring-context/src/test/java/org/springframework/context/annotation/configuration/BeanMethodQualificationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -22,6 +22,7 @@
 import org.junit.Test;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
@@ -77,10 +78,27 @@ public void testScopedProxy() {
 	}
 
 	@Test
-	public void testCustom() {
+	public void testCustomWithLazyResolution() {
 		AnnotationConfigApplicationContext ctx =
 				new AnnotationConfigApplicationContext(CustomConfig.class, CustomPojo.class);
 		assertFalse(ctx.getBeanFactory().containsSingleton("testBean1"));
+		assertFalse(ctx.getBeanFactory().containsSingleton("testBean2"));
+		assertTrue(BeanFactoryAnnotationUtils.isQualifierMatch(value -> value.equals("boring"),
+				"testBean2", ctx.getDefaultListableBeanFactory()));
+		CustomPojo pojo = ctx.getBean(CustomPojo.class);
+		assertThat(pojo.testBean.getName(), equalTo("interesting"));
+	}
+
+	@Test
+	public void testCustomWithEarlyResolution() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.register(CustomConfig.class, CustomPojo.class);
+		ctx.refresh();
+		assertFalse(ctx.getBeanFactory().containsSingleton("testBean1"));
+		assertFalse(ctx.getBeanFactory().containsSingleton("testBean2"));
+		ctx.getBean("testBean2");
+		assertTrue(BeanFactoryAnnotationUtils.isQualifierMatch(value -> value.equals("boring"),
+				"testBean2", ctx.getDefaultListableBeanFactory()));
 		CustomPojo pojo = ctx.getBean(CustomPojo.class);
 		assertThat(pojo.testBean.getName(), equalTo("interesting"));
 	}
@@ -94,6 +112,7 @@ public void testCustomWithAsm() {
 		ctx.registerBeanDefinition("customPojo", customPojo);
 		ctx.refresh();
 		assertFalse(ctx.getBeanFactory().containsSingleton("testBean1"));
+		assertFalse(ctx.getBeanFactory().containsSingleton("testBean2"));
 		CustomPojo pojo = ctx.getBean(CustomPojo.class);
 		assertThat(pojo.testBean.getName(), equalTo("interesting"));
 	}
@@ -171,7 +190,7 @@ public TestBean testBean1() {
 			return new TestBean("interesting");
 		}
 
-		@Bean @Qualifier("boring")
+		@Bean @Qualifier("boring") @Lazy
 		public TestBean testBean2() {
 			return new TestBean("boring");
 		}