@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
-	 * with the specified name
+	 * @throws NoSuchBeanDefinitionException if there is no bean 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.
-	 * {@code null} is disallowed.
+	 * @param requiredType type the bean must match; can be an interface or superclass
 	 * @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
 	//---------------------------------------------------------------------