@Resource provides dependency descriptor for resolving beans by name

Closes gh-22359

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -133,8 +133,7 @@ public interface BeanFactory {
 	 * Will ask the parent factory if the bean cannot be found in this factory instance.
 	 * @param name the name of the bean to retrieve
 	 * @return an instance of the bean
-	 * @throws NoSuchBeanDefinitionException if there is no bean definition
+	 * @throws NoSuchBeanDefinitionException if there is no bean with the specified name
-	 * with the specified name
 	 * @throws BeansException if the bean could not be obtained
 	 */
 	Object getBean(String name) throws BeansException;

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -29,6 +29,8 @@ import org.springframework.util.ObjectUtils;
 /**
  * A simple descriptor for an injection point, pointing to a method/constructor
  * parameter or a field. Exposed by {@link UnsatisfiedDependencyException}.
+ * Also available as an argument for factory methods, reacting to the
+ * requesting injection point for building a customized bean instance.
  *
  * @author Juergen Hoeller
  * @since 4.3

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -337,8 +337,7 @@ public interface AutowireCapableBeanFactory extends BeanFactory {
 	 * including its bean name.
 	 * <p>This is effectively a variant of {@link #getBean(Class)} which preserves the
 	 * bean name of the matching instance.
-	 * @param requiredType type the bean must match; can be an interface or superclass.
+	 * @param requiredType type the bean must match; can be an interface or superclass
-	 * {@code null} is disallowed.
 	 * @return the bean name plus bean instance
 	 * @throws NoSuchBeanDefinitionException if no matching bean was found
 	 * @throws NoUniqueBeanDefinitionException if more than one matching bean was found
@@ -348,6 +347,22 @@ public interface AutowireCapableBeanFactory extends BeanFactory {
 	 */
 	<T> NamedBeanHolder<T> resolveNamedBean(Class<T> requiredType) throws BeansException;
 
+	/**
+	 * Resolve a bean instance for the given bean name, providing a dependency descriptor
+	 * for exposure to target factory methods.
+	 * <p>This is effectively a variant of {@link #getBean(String, Class)} which supports
+	 * factory methods with an {@link org.springframework.beans.factory.InjectionPoint}
+	 * argument.
+	 * @param name the name of the bean to look up
+	 * @param descriptor the dependency descriptor for the requesting injection point
+	 * @return the corresponding bean instance
+	 * @throws NoSuchBeanDefinitionException if there is no bean with the specified name
+	 * @throws BeansException if the bean could not be created
+	 * @since 5.1.5
+	 * @see #getBean(String, Class)
+	 */
+	Object resolveBeanByName(String name, DependencyDescriptor descriptor) throws BeansException;
+
 	/**
 	 * Resolve the specified dependency against the beans defined in this factory.
 	 * @param descriptor the descriptor for the dependency (field/method/constructor)

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -58,6 +58,7 @@ import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.BeanNameAware;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.factory.InjectionPoint;
 import org.springframework.beans.factory.UnsatisfiedDependencyException;
 import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -337,12 +338,6 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 		return initializeBean(beanName, existingBean, bd);
 	}
 
-	@Override
-	@Nullable
-	public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException {
-		return resolveDependency(descriptor, requestingBeanName, null, null);
-	}
-
 
 	//-------------------------------------------------------------------------
 	// Specialized methods for fine-grained control over the bean lifecycle
@@ -446,6 +441,28 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 	}
 
 
+	//-------------------------------------------------------------------------
+	// Delegate methods for resolving injection points
+	//-------------------------------------------------------------------------
+
+	@Override
+	public Object resolveBeanByName(String name, DependencyDescriptor descriptor) {
+		InjectionPoint previousInjectionPoint = ConstructorResolver.setCurrentInjectionPoint(descriptor);
+		try {
+			return getBean(name, descriptor.getDependencyType());
+		}
+		finally {
+			ConstructorResolver.setCurrentInjectionPoint(previousInjectionPoint);
+		}
+	}
+
+	@Override
+	@Nullable
+	public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException {
+		return resolveDependency(descriptor, requestingBeanName, null, null);
+	}
+
+
 	//---------------------------------------------------------------------
 	// Implementation of relevant AbstractBeanFactory template methods
 	//---------------------------------------------------------------------

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -512,15 +512,21 @@ public class CommonAnnotationBeanPostProcessor extends InitDestroyAnnotationBean
 		Set<String> autowiredBeanNames;
 		String name = element.name;
 
-		if (this.fallbackToDefaultTypeMatch && element.isDefaultName &&
+		if (factory instanceof AutowireCapableBeanFactory) {
-				factory instanceof AutowireCapableBeanFactory && !factory.containsBean(name)) {
+			AutowireCapableBeanFactory beanFactory = (AutowireCapableBeanFactory) factory;
+			DependencyDescriptor descriptor = element.getDependencyDescriptor();
+			if (this.fallbackToDefaultTypeMatch && element.isDefaultName && !factory.containsBean(name)) {
 				autowiredBeanNames = new LinkedHashSet<>();
-			resource = ((AutowireCapableBeanFactory) factory).resolveDependency(
+				resource = beanFactory.resolveDependency(descriptor, requestingBeanName, autowiredBeanNames, null);
-					element.getDependencyDescriptor(), requestingBeanName, autowiredBeanNames, null);
 				if (resource == null) {
 					throw new NoSuchBeanDefinitionException(element.getLookupType(), "No resolvable resource object");
 				}
 			}
+			else {
+				resource = beanFactory.resolveBeanByName(name, descriptor);
+				autowiredBeanNames = Collections.singleton(name);
+			}
+		}
 		else {
 			resource = factory.getBean(name, element.lookupType);
 			autowiredBeanNames = Collections.singleton(name);

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 import java.util.function.Supplier;
+import javax.annotation.Resource;
 import javax.inject.Provider;
 
 import org.junit.Rule;
@@ -228,6 +229,22 @@ public class ConfigurationClassProcessingTests {
 		ctx.close();
 	}
 
+	@Test
+	public void configurationWithAdaptiveResourcePrototypes() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		ctx.register(ConfigWithPrototypeBean.class, AdaptiveResourceInjectionPoints.class);
+		ctx.refresh();
+
+		AdaptiveResourceInjectionPoints adaptive = ctx.getBean(AdaptiveResourceInjectionPoints.class);
+		assertEquals("adaptiveInjectionPoint1", adaptive.adaptiveInjectionPoint1.getName());
+		assertEquals("setAdaptiveInjectionPoint2", adaptive.adaptiveInjectionPoint2.getName());
+
+		adaptive = ctx.getBean(AdaptiveResourceInjectionPoints.class);
+		assertEquals("adaptiveInjectionPoint1", adaptive.adaptiveInjectionPoint1.getName());
+		assertEquals("setAdaptiveInjectionPoint2", adaptive.adaptiveInjectionPoint2.getName());
+		ctx.close();
+	}
+
 	@Test
 	public void configurationWithPostProcessor() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
@@ -444,6 +461,21 @@ public class ConfigurationClassProcessingTests {
 	}
 
 
+	@Scope("prototype")
+	static class AdaptiveResourceInjectionPoints {
+
+		@Resource(name = "adaptive1")
+		public TestBean adaptiveInjectionPoint1;
+
+		public TestBean adaptiveInjectionPoint2;
+
+		@Resource(name = "adaptive2")
+		public void setAdaptiveInjectionPoint2(TestBean adaptiveInjectionPoint2) {
+			this.adaptiveInjectionPoint2 = adaptiveInjectionPoint2;
+		}
+	}
+
+
 	static class ConfigWithPostProcessor extends ConfigWithPrototypeBean {
 
 		@Value("${myProp}")

spring-test/src/main/java/org/springframework/test/web/servlet/setup/StubWebApplicationContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -411,6 +411,11 @@ class StubWebApplicationContext implements WebApplicationContext {
 			throw new UnsupportedOperationException("Dependency resolution not supported");
 		}
 
+		@Override
+		public Object resolveBeanByName(String name, DependencyDescriptor descriptor) throws BeansException {
+			throw new UnsupportedOperationException("Dependency resolution not supported");
+		}
+
 		@Override
 		@Nullable
 		public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) {