Cache bean type next to primary bean names (on singleton creation)

This avoids singleton access for type checks in hasPrimaryConflict.

Closes gh-35330

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

@@ -58,6 +58,7 @@ import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.BeanNotOfRequiredTypeException;
 import org.springframework.beans.factory.CannotLoadBeanClassException;
+import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.factory.InjectionPoint;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
@@ -196,8 +197,8 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 	/** Map from bean name to merged BeanDefinitionHolder. */
 	private final Map<String, BeanDefinitionHolder> mergedBeanDefinitionHolders = new ConcurrentHashMap<>(256);
 
-	/** Set of bean definition names with a primary marker. */
+	/** Map of bean definition names with a primary marker plus corresponding type. */
-	private final Set<String> primaryBeanNames = ConcurrentHashMap.newKeySet(16);
+	private final Map<String, Class<?>> primaryBeanNamesWithType = new ConcurrentHashMap<>(16);
 
 	/** Map of singleton and non-singleton bean names, keyed by dependency type. */
 	private final Map<Class<?>, String[]> allBeanNamesByType = new ConcurrentHashMap<>(64);
@@ -1037,7 +1038,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 	protected void cacheMergedBeanDefinition(RootBeanDefinition mbd, String beanName) {
 		super.cacheMergedBeanDefinition(mbd, beanName);
 		if (mbd.isPrimary()) {
-			this.primaryBeanNames.add(beanName);
+			this.primaryBeanNamesWithType.put(beanName, Void.class);
 		}
 	}
 
@@ -1313,7 +1314,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 
 		// Cache a primary marker for the given bean.
 		if (beanDefinition.isPrimary()) {
-			this.primaryBeanNames.add(beanName);
+			this.primaryBeanNamesWithType.put(beanName, Void.class);
 		}
 	}
 
@@ -1405,7 +1406,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 		destroySingleton(beanName);
 
 		// Remove a cached primary marker for the given bean.
-		this.primaryBeanNames.remove(beanName);
+		this.primaryBeanNamesWithType.remove(beanName);
 
 		// Notify all post-processors that the specified bean definition has been reset.
 		for (MergedBeanDefinitionPostProcessor processor : getBeanPostProcessorCache().mergedDefinition) {
@@ -1458,9 +1459,18 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 	@Override
 	protected void addSingleton(String beanName, Object singletonObject) {
 		super.addSingleton(beanName, singletonObject);
+
 		Predicate<Class<?>> filter = (beanType -> beanType != Object.class && beanType.isInstance(singletonObject));
 		this.allBeanNamesByType.keySet().removeIf(filter);
 		this.singletonBeanNamesByType.keySet().removeIf(filter);
+
+		if (this.primaryBeanNamesWithType.containsKey(beanName) && singletonObject.getClass() != NullBean.class) {
+			Class<?> beanType = (singletonObject instanceof FactoryBean<?> fb ?
+					getTypeForFactoryBean(fb) : singletonObject.getClass());
+			if (beanType != null) {
+				this.primaryBeanNamesWithType.put(beanName, beanType);
+			}
+		}
 	}
 
 	@Override
@@ -2268,8 +2278,12 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 	 * not matching the given bean name.
 	 */
 	private boolean hasPrimaryConflict(String beanName, Class<?> dependencyType) {
-		for (String candidate : this.primaryBeanNames) {
+		for (Map.Entry<String, Class<?>> candidate : this.primaryBeanNamesWithType.entrySet()) {
-			if (isTypeMatch(candidate, dependencyType) && !candidate.equals(beanName)) {
+			String candidateName = candidate.getKey();
+			Class<?> candidateType = candidate.getValue();
+			if (!candidateName.equals(beanName) && (candidateType != Void.class ?
+					dependencyType.isAssignableFrom(candidateType) :  // cached singleton class for primary bean
+					isTypeMatch(candidateName, dependencyType))) {  // not instantiated yet or not a singleton
 				return true;
 			}
 		}