diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java b/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java
index 81e44240497..7d29ebc9ca5 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultSingletonBeanRegistry.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.
@@ -178,13 +178,13 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 	 */
 	@Nullable
 	protected Object getSingleton(String beanName, boolean allowEarlyReference) {
-		// Quick check for existing instance without full singleton lock
+		// Quick check for existing instance without full singleton lock.
 		Object singletonObject = this.singletonObjects.get(beanName);
 		if (singletonObject == null && isSingletonCurrentlyInCreation(beanName)) {
 			singletonObject = this.earlySingletonObjects.get(beanName);
 			if (singletonObject == null && allowEarlyReference) {
 				synchronized (this.singletonObjects) {
-					// Consistent creation of early reference within full singleton lock
+					// Consistent creation of early reference within full singleton lock.
 					singletonObject = this.singletonObjects.get(beanName);
 					if (singletonObject == null) {
 						singletonObject = this.earlySingletonObjects.get(beanName);
diff --git a/spring-core/src/main/java/org/springframework/core/SpringProperties.java b/spring-core/src/main/java/org/springframework/core/SpringProperties.java
index 3cb1cd51ebf..ac4a72776dd 100644
--- a/spring-core/src/main/java/org/springframework/core/SpringProperties.java
+++ b/spring-core/src/main/java/org/springframework/core/SpringProperties.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.
@@ -117,7 +117,7 @@ public final class SpringProperties {
 	 * @param key the property key
 	 */
 	public static void setFlag(String key) {
-		localProperties.put(key, Boolean.TRUE.toString());
+		localProperties.setProperty(key, Boolean.TRUE.toString());
 	}
 
 	/**