Expose resolveAutowireCandidates method with basic candidate filtering

DependencyObjectProvider is aligned to check basic autowire-candidate status even in case of custom filtering.

Closes gh-34203

Author: jhoeller

spring-beans/src/main/java/org/springframework/beans/factory/BeanFactoryUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -39,10 +39,14 @@
  * (which the methods defined on the ListableBeanFactory interface don't,
  * in contrast to the methods defined on the BeanFactory interface).
  *
+ * <p><b>NOTE:</b> It is generally preferable to use {@link ObjectProvider#stream()}
+ * via {@link BeanFactory#getBeanProvider} instead of this utility class.
+ *
  * @author Rod Johnson
  * @author Juergen Hoeller
  * @author Chris Beams
  * @since 04.07.2003
+ * @see BeanFactory#getBeanProvider
  */
 public abstract class BeanFactoryUtils {
 
@@ -308,7 +312,7 @@ public static String[] beanNamesForAnnotationIncludingAncestors(
 	 * 'replacing' beans by explicitly choosing the same bean name in a child factory;
 	 * the bean in the ancestor factory won't be visible then, not even for by-type lookups.
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @return the Map of matching bean instances, or an empty Map if none
 	 * @throws BeansException if a bean could not be created
 	 * @see ListableBeanFactory#getBeansOfType(Class)
@@ -347,7 +351,7 @@ public static <T> Map<String, T> beansOfTypeIncludingAncestors(ListableBeanFacto
 	 * 'replacing' beans by explicitly choosing the same bean name in a child factory;
 	 * the bean in the ancestor factory won't be visible then, not even for by-type lookups.
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @param includeNonSingletons whether to include prototype or scoped beans too
 	 * or just singletons (also applies to FactoryBeans)
 	 * @param allowEagerInit whether to initialize <i>lazy-init singletons</i> and
@@ -395,7 +399,7 @@ public static <T> Map<String, T> beansOfTypeIncludingAncestors(
 	 * 'replacing' beans by explicitly choosing the same bean name in a child factory;
 	 * the bean in the ancestor factory won't be visible then, not even for by-type lookups.
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @return the matching bean instance
 	 * @throws NoSuchBeanDefinitionException if no bean of the given type was found
 	 * @throws NoUniqueBeanDefinitionException if more than one bean of the given type was found
@@ -425,7 +429,7 @@ public static <T> T beanOfTypeIncludingAncestors(ListableBeanFactory lbf, Class<
 	 * 'replacing' beans by explicitly choosing the same bean name in a child factory;
 	 * the bean in the ancestor factory won't be visible then, not even for by-type lookups.
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @param includeNonSingletons whether to include prototype or scoped beans too
 	 * or just singletons (also applies to FactoryBeans)
 	 * @param allowEagerInit whether to initialize <i>lazy-init singletons</i> and
@@ -457,7 +461,7 @@ public static <T> T beanOfTypeIncludingAncestors(
 	 * <p>This version of {@code beanOfType} automatically includes
 	 * prototypes and FactoryBeans.
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @return the matching bean instance
 	 * @throws NoSuchBeanDefinitionException if no bean of the given type was found
 	 * @throws NoUniqueBeanDefinitionException if more than one bean of the given type was found
@@ -481,7 +485,7 @@ public static <T> T beanOfType(ListableBeanFactory lbf, Class<T> type) throws Be
 	 * only raw FactoryBeans will be checked (which doesn't require initialization
 	 * of each FactoryBean).
 	 * @param lbf the bean factory
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @param includeNonSingletons whether to include prototype or scoped beans too
 	 * or just singletons (also applies to FactoryBeans)
 	 * @param allowEagerInit whether to initialize <i>lazy-init singletons</i> and
@@ -529,7 +533,7 @@ private static String[] mergeNamesWithParent(String[] result, String[] parentRes
 
 	/**
 	 * Extract a unique bean for the given type from the given Map of matching beans.
-	 * @param type type of bean to match
+	 * @param type the type of bean to match
 	 * @param matchingBeans all matching beans found
 	 * @return the unique bean instance
 	 * @throws NoSuchBeanDefinitionException if no bean of the given type was found

spring-beans/src/main/java/org/springframework/beans/factory/ObjectProvider.java

@@ -55,10 +55,13 @@
 public interface ObjectProvider<T> extends ObjectFactory<T>, Iterable<T> {
 
 	/**
-	 * A predicate for unfiltered type matches.
+	 * A predicate for unfiltered type matches, including non-default candidates
+	 * but still excluding non-autowire candidates when used on injection points.
 	 * @since 6.2.3
 	 * @see #stream(Predicate)
 	 * @see #orderedStream(Predicate)
+	 * @see org.springframework.beans.factory.config.BeanDefinition#isAutowireCandidate()
+	 * @see org.springframework.beans.factory.support.AbstractBeanDefinition#isDefaultCandidate()
 	 */
 	Predicate<Class<?>> UNFILTERED = (clazz -> true);
 
@@ -210,7 +213,7 @@ default Iterator<T> iterator() {
 	 * without specific ordering guarantees (but typically in registration order).
 	 * <p>Note: The result may be filtered by default according to qualifiers on the
 	 * injection point versus target beans and the general autowire candidate status
-	 * of matching beans. For custom filtering against the raw type matches, use
+	 * of matching beans. For custom filtering against type-matching candidates, use
 	 * {@link #stream(Predicate)} instead (potentially with {@link #UNFILTERED}).
 	 * @since 5.1
 	 * @see #iterator()
@@ -235,7 +238,7 @@ default Stream<T> stream() {
 	 * if necessary.
 	 * <p>Note: The result may be filtered by default according to qualifiers on the
 	 * injection point versus target beans and the general autowire candidate status
-	 * of matching beans. For custom filtering against the raw type matches, use
+	 * of matching beans. For custom filtering against type-matching candidates, use
 	 * {@link #stream(Predicate)} instead (potentially with {@link #UNFILTERED}).
 	 * @since 5.1
 	 * @see #stream()

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -33,7 +33,9 @@
 import java.util.Set;
 
 import org.springframework.beans.BeanMetadataElement;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.ObjectFactory;
+import org.springframework.beans.factory.config.ConfigurableBeanFactory;
 import org.springframework.beans.factory.config.TypedStringValue;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -259,6 +261,24 @@ else if (arg instanceof TypedStringValue typedValue) {
 		return method.getReturnType();
 	}
 
+	/**
+	 * Check the autowire-candidate status for the specified bean.
+	 * @param beanFactory the bean factory
+	 * @param beanName the name of the bean to check
+	 * @return whether the specified bean qualifies as an autowire candidate
+	 * @since 6.2.3
+	 * @see org.springframework.beans.factory.config.BeanDefinition#isAutowireCandidate()
+	 */
+	public static boolean isAutowireCandidate(ConfigurableBeanFactory beanFactory, String beanName) {
+		try {
+			return beanFactory.getMergedBeanDefinition(beanName).isAutowireCandidate();
+		}
+		catch (NoSuchBeanDefinitionException ex) {
+			// A manually registered singleton instance not backed by a BeanDefinition.
+			return true;
+		}
+	}
+
 
 	/**
 	 * Reflective {@link InvocationHandler} for lazy access to the current target object.

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

@@ -2516,6 +2516,7 @@ private Stream<Object> resolveStream(boolean ordered) {
 		@Override
 		public Stream<Object> stream(Predicate<Class<?>> customFilter) {
 			return Arrays.stream(getBeanNamesForTypedStream(this.descriptor.getResolvableType(), true))
+					.filter(name -> AutowireUtils.isAutowireCandidate(DefaultListableBeanFactory.this, name))
 					.filter(name -> customFilter.test(getType(name)))
 					.map(name -> getBean(name))
 					.filter(bean -> !(bean instanceof NullBean));
@@ -2529,7 +2530,8 @@ public Stream<Object> orderedStream(Predicate<Class<?>> customFilter) {
 			}
 			Map<String, Object> matchingBeans = CollectionUtils.newLinkedHashMap(beanNames.length);
 			for (String beanName : beanNames) {
-				if (customFilter.test(getType(beanName))) {
+				if (AutowireUtils.isAutowireCandidate(DefaultListableBeanFactory.this, beanName) &&
+						customFilter.test(getType(beanName))) {
 					Object beanInstance = getBean(beanName);
 					if (!(beanInstance instanceof NullBean)) {
 						matchingBeans.put(beanName, beanInstance);

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -16,9 +16,13 @@
 
 package org.springframework.beans.factory.support;
 
-import org.springframework.beans.factory.config.BeanDefinitionHolder;
-import org.springframework.beans.factory.config.DependencyDescriptor;
-import org.springframework.lang.Nullable;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactoryUtils;
+import org.springframework.beans.factory.ListableBeanFactory;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 
 /**
  * {@link AutowireCandidateResolver} implementation to use when no annotation
@@ -36,46 +40,6 @@ public class SimpleAutowireCandidateResolver implements AutowireCandidateResolve
 	 */
 	public static final SimpleAutowireCandidateResolver INSTANCE = new SimpleAutowireCandidateResolver();
 
-
-	@Override
-	public boolean isAutowireCandidate(BeanDefinitionHolder bdHolder, DependencyDescriptor descriptor) {
-		return bdHolder.getBeanDefinition().isAutowireCandidate();
-	}
-
-	@Override
-	public boolean isRequired(DependencyDescriptor descriptor) {
-		return descriptor.isRequired();
-	}
-
-	@Override
-	public boolean hasQualifier(DependencyDescriptor descriptor) {
-		return false;
-	}
-
-	@Override
-	@Nullable
-	public String getSuggestedName(DependencyDescriptor descriptor) {
-		return null;
-	}
-
-	@Override
-	@Nullable
-	public Object getSuggestedValue(DependencyDescriptor descriptor) {
-		return null;
-	}
-
-	@Override
-	@Nullable
-	public Object getLazyResolutionProxyIfNecessary(DependencyDescriptor descriptor, @Nullable String beanName) {
-		return null;
-	}
-
-	@Override
-	@Nullable
-	public Class<?> getLazyResolutionProxyClass(DependencyDescriptor descriptor, @Nullable String beanName) {
-		return null;
-	}
-
 	/**
 	 * This implementation returns {@code this} as-is.
 	 * @see #INSTANCE
@@ -85,4 +49,31 @@ public AutowireCandidateResolver cloneIfNecessary() {
 		return this;
 	}
 
+
+	/**
+	 * Resolve a map of all beans of the given type, also picking up beans defined in
+	 * ancestor bean factories, with the specific condition that each bean actually
+	 * has autowire candidate status. This matches simple injection point resolution
+	 * as implemented by this {@link AutowireCandidateResolver} strategy, including
+	 * beans which are not marked as default candidates but excluding beans which
+	 * are not even marked as autowire candidates.
+	 * @param lbf the bean factory
+	 * @param type the type of bean to match
+	 * @return the Map of matching bean instances, or an empty Map if none
+	 * @throws BeansException if a bean could not be created
+	 * @since 6.2.3
+	 * @see BeanFactoryUtils#beansOfTypeIncludingAncestors(ListableBeanFactory, Class)
+	 * @see org.springframework.beans.factory.config.BeanDefinition#isAutowireCandidate()
+	 * @see AbstractBeanDefinition#isDefaultCandidate()
+	 */
+	public static <T> Map<String, T> resolveAutowireCandidates(ConfigurableListableBeanFactory lbf, Class<T> type) {
+		Map<String, T> candidates = new LinkedHashMap<>();
+		for (String beanName : BeanFactoryUtils.beanNamesForTypeIncludingAncestors(lbf, type)) {
+			if (AutowireUtils.isAutowireCandidate(lbf, beanName)) {
+				candidates.put(beanName, lbf.getBean(beanName, type));
+			}
+		}
+		return candidates;
+	}
+
 }

spring-beans/src/test/java/org/springframework/beans/factory/annotation/AutowiredAnnotationBeanPostProcessorTests.java

@@ -48,6 +48,7 @@
 
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.BeanNameAware;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.FactoryBean;
@@ -64,6 +65,7 @@
 import org.springframework.beans.factory.support.DefaultListableBeanFactory;
 import org.springframework.beans.factory.support.GenericBeanDefinition;
 import org.springframework.beans.factory.support.RootBeanDefinition;
+import org.springframework.beans.factory.support.SimpleAutowireCandidateResolver;
 import org.springframework.beans.testfixture.beans.DerivedTestBean;
 import org.springframework.beans.testfixture.beans.ITestBean;
 import org.springframework.beans.testfixture.beans.IndexedTestBean;
@@ -1756,14 +1758,17 @@ void objectProviderInjectionWithNonCandidatesInStream() {
 		RootBeanDefinition tb2 = new RootBeanDefinition(TestBeanFactory.class);
 		tb2.setFactoryMethodName("newTestBean2");
 		bf.registerBeanDefinition("testBean2", tb2);
+
+		DefaultListableBeanFactory parent = new DefaultListableBeanFactory();
 		RootBeanDefinition tb3 = new RootBeanDefinition(TestBean.class);
 		tb3.setAutowireCandidate(false);
 		tb3.setLazyInit(true);
-		bf.registerBeanDefinition("testBean3", tb3);
+		parent.registerBeanDefinition("testBean3", tb3);
 		RootBeanDefinition tb4 = new RootBeanDefinition(DerivedTestBean.class);
 		tb4.setDefaultCandidate(false);
 		tb4.setLazyInit(true);
-		bf.registerBeanDefinition("testBean4", tb4);
+		parent.registerBeanDefinition("testBean4", tb4);
+		bf.setParentBeanFactory(parent);
 
 		ObjectProviderInjectionBean bean = bf.getBean("annotatedBean", ObjectProviderInjectionBean.class);
 		assertThat(bean.streamTestBeans()).containsExactly(bf.getBean("testBean1", TestBean.class),
@@ -1772,16 +1777,19 @@ void objectProviderInjectionWithNonCandidatesInStream() {
 				bf.getBean("testBean1", TestBean.class));
 		assertThat(bf.containsSingleton("testBean3")).isFalse();
 		assertThat(bean.plainTestBeans()).containsExactly(bf.getBean("testBean1", TestBean.class),
-				bf.getBean("testBean2", TestBean.class), bf.getBean("testBean3", TestBean.class));
+				bf.getBean("testBean2", TestBean.class));
 		assertThat(bean.plainTestBeansInOrder()).containsExactly(bf.getBean("testBean2", TestBean.class),
-				bf.getBean("testBean1", TestBean.class), bf.getBean("testBean3", TestBean.class));
+				bf.getBean("testBean1", TestBean.class));
 		assertThat(bf.containsSingleton("testBean4")).isFalse();
 		assertThat(bean.allTestBeans()).containsExactly(bf.getBean("testBean1", TestBean.class),
-				bf.getBean("testBean2", TestBean.class), bf.getBean("testBean3", TestBean.class),
-				bf.getBean("testBean4", TestBean.class));
+				bf.getBean("testBean2", TestBean.class), bf.getBean("testBean4", TestBean.class));
 		assertThat(bean.allTestBeansInOrder()).containsExactly(bf.getBean("testBean2", TestBean.class),
-				bf.getBean("testBean1", TestBean.class), bf.getBean("testBean3", TestBean.class),
-				bf.getBean("testBean4", TestBean.class));
+				bf.getBean("testBean1", TestBean.class), bf.getBean("testBean4", TestBean.class));
+
+		Map<String, TestBean> typeMatches = BeanFactoryUtils.beansOfTypeIncludingAncestors(bf, TestBean.class);
+		assertThat(typeMatches.remove("testBean3")).isNotNull();
+		Map<String, TestBean> candidates = SimpleAutowireCandidateResolver.resolveAutowireCandidates(bf, TestBean.class);
+		assertThat(candidates).containsExactlyEntriesOf(candidates);
 	}
 
 	@Test