Add RootBeanDefinition constructor that accepts a ResolvableType

Add a new convenience constructor to `RootBeanDefinition` that allow
it to be created with a `ResolvableType`.

Closes gh-28418

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -125,8 +125,7 @@ public final class BeanDefinitionBuilder {
 	 * @since 5.3.9
 	 */
 	public static <T> BeanDefinitionBuilder rootBeanDefinition(ResolvableType beanType, Supplier<T> instanceSupplier) {
-		RootBeanDefinition beanDefinition = new RootBeanDefinition();
+		RootBeanDefinition beanDefinition = new RootBeanDefinition(beanType);
-		beanDefinition.setTargetType(beanType);
 		beanDefinition.setInstanceSupplier(instanceSupplier);
 		return new BeanDefinitionBuilder(beanDefinition);
 	}

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

@@ -139,7 +139,6 @@ public class RootBeanDefinition extends AbstractBeanDefinition {
 	 * @see #setPropertyValues
 	 */
 	public RootBeanDefinition() {
-		super();
 	}
 
 	/**
@@ -148,10 +147,18 @@ public class RootBeanDefinition extends AbstractBeanDefinition {
 	 * @see #setBeanClass
 	 */
 	public RootBeanDefinition(@Nullable Class<?> beanClass) {
-		super();
 		setBeanClass(beanClass);
 	}
 
+	/**
+	 * Create a new RootBeanDefinition for a singleton.
+	 * @param beanType the type of bean to instantiate
+	 * @see #setTargetType(ResolvableType)
+	 */
+	public RootBeanDefinition(@Nullable ResolvableType beanType) {
+		setTargetType(beanType);
+	}
+
 	/**
 	 * Create a new RootBeanDefinition for a singleton bean, constructing each instance
 	 * through calling the given supplier (possibly a lambda or method reference).
@@ -193,7 +200,6 @@ public class RootBeanDefinition extends AbstractBeanDefinition {
 	 * (not applicable to autowiring a constructor, thus ignored there)
 	 */
 	public RootBeanDefinition(@Nullable Class<?> beanClass, int autowireMode, boolean dependencyCheck) {
-		super();
 		setBeanClass(beanClass);
 		setAutowireMode(autowireMode);
 		if (dependencyCheck && getResolvedAutowireMode() != AUTOWIRE_CONSTRUCTOR) {