diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedList.java b/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedList.java
index 2814670194..fbf3970719 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedList.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedList.java
@@ -17,7 +17,7 @@
 package org.springframework.beans.factory.support;
 
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import org.springframework.beans.BeanMetadataElement;
@@ -31,6 +31,8 @@ import org.springframework.lang.Nullable;
  * @author Rod Johnson
  * @author Rob Harrop
  * @author Juergen Hoeller
+ * @author Stephane Nicoll
+ * @author Sam Brannen
  * @since 27.05.2003
  * @param <E> the element type
  */
@@ -55,16 +57,16 @@ public class ManagedList<E> extends ArrayList<E> implements Mergeable, BeanMetad
 
 
 	/**
-	 * Return a new instance containing an arbitrary number of elements.
+	 * Create a new instance containing an arbitrary number of elements.
 	 * @param elements the elements to be contained in the list
 	 * @param <E> the {@code List}'s element type
-	 * @return a {@code List} containing the specified elements
+	 * @return a {@code ManagedList} containing the specified elements
 	 * @since 5.3.16
 	 */
-	@SuppressWarnings("unchecked")
+	@SafeVarargs
 	public static <E> ManagedList<E> of(E... elements) {
 		ManagedList<E> list = new ManagedList<>();
-		list.addAll(Arrays.asList(elements));
+		Collections.addAll(list, elements);
 		return list;
 	}
 
diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedSet.java b/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedSet.java
index f5c7246237..8bc4152aea 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedSet.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/support/ManagedSet.java
@@ -16,7 +16,7 @@
 
 package org.springframework.beans.factory.support;
 
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.Set;
 
@@ -30,6 +30,8 @@ import org.springframework.lang.Nullable;
  *
  * @author Juergen Hoeller
  * @author Rob Harrop
+ * @author Stephane Nicoll
+ * @author Sam Brannen
  * @since 21.01.2004
  * @param <E> the element type
  */
@@ -54,16 +56,16 @@ public class ManagedSet<E> extends LinkedHashSet<E> implements Mergeable, BeanMe
 
 
 	/**
-	 * Return a new instance containing an arbitrary number of elements.
+	 * Create a new instance containing an arbitrary number of elements.
 	 * @param elements the elements to be contained in the set
 	 * @param <E> the {@code Set}'s element type
-	 * @return a {@code Set} containing the specified elements
+	 * @return a {@code ManagedSet} containing the specified elements
 	 * @since 5.3.16
 	 */
-	@SuppressWarnings("unchecked")
+	@SafeVarargs
 	public static <E> ManagedSet<E> of(E... elements) {
 		ManagedSet<E> set = new ManagedSet<>();
-		set.addAll(Arrays.asList(elements));
+		Collections.addAll(set, elements);
 		return set;
 	}
 
diff --git a/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedListTests.java b/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedListTests.java
index 420226d173..9d8a1cbe36 100644
--- a/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedListTests.java
+++ b/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedListTests.java
@@ -25,61 +25,61 @@ import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException
 import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
+ * Unit tests for {@link ManagedList}.
+ *
  * @author Rick Evans
  * @author Juergen Hoeller
  * @author Sam Brannen
  */
 @SuppressWarnings({ "rawtypes", "unchecked" })
-public class ManagedListTests {
+class ManagedListTests {
 
 	@Test
-	public void mergeSunnyDay() {
+	void mergeSunnyDay() {
 		ManagedList parent = ManagedList.of("one", "two");
 		ManagedList child = ManagedList.of("three");
 		child.setMergeEnabled(true);
 		List mergedList = child.merge(parent);
-		assertThat(mergedList.size()).as("merge() obviously did not work.").isEqualTo(3);
+		assertThat(mergedList).as("merge() obviously did not work.").containsExactly("one", "two", "three");
 	}
 
 	@Test
-	public void mergeWithNullParent() {
+	void mergeWithNullParent() {
 		ManagedList child = ManagedList.of("one");
 		child.setMergeEnabled(true);
 		assertThat(child.merge(null)).isSameAs(child);
 	}
 
 	@Test
-	public void mergeNotAllowedWhenMergeNotEnabled() {
+	void mergeNotAllowedWhenMergeNotEnabled() {
 		ManagedList child = new ManagedList();
-		assertThatIllegalStateException().isThrownBy(() ->
-				child.merge(null));
+		assertThatIllegalStateException().isThrownBy(() -> child.merge(null));
 	}
 
 	@Test
-	public void mergeWithNonCompatibleParentType() {
+	void mergeWithIncompatibleParentType() {
 		ManagedList child = ManagedList.of("one");
 		child.setMergeEnabled(true);
-		assertThatIllegalArgumentException().isThrownBy(() ->
-				child.merge("hello"));
+		assertThatIllegalArgumentException().isThrownBy(() -> child.merge("hello"));
 	}
 
 	@Test
-	public void mergeEmptyChild() {
+	void mergeEmptyChild() {
 		ManagedList parent = ManagedList.of("one", "two");
 		ManagedList child = new ManagedList();
 		child.setMergeEnabled(true);
 		List mergedList = child.merge(parent);
-		assertThat(mergedList.size()).as("merge() obviously did not work.").isEqualTo(2);
+		assertThat(mergedList).as("merge() obviously did not work.").containsExactly("one", "two");
 	}
 
 	@Test
-	public void mergeChildValuesOverrideTheParents() {
+	void mergedChildValuesDoNotOverrideTheParents() {
 		// doesn't make much sense in the context of a list...
 		ManagedList parent = ManagedList.of("one", "two");
 		ManagedList child = ManagedList.of("one");
 		child.setMergeEnabled(true);
 		List mergedList = child.merge(parent);
-		assertThat(mergedList.size()).as("merge() obviously did not work.").isEqualTo(3);
+		assertThat(mergedList).as("merge() obviously did not work.").containsExactly("one", "two", "one");
 	}
 
 }
diff --git a/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedSetTests.java b/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedSetTests.java
index c11a63a6da..01f330f1c5 100644
--- a/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedSetTests.java
+++ b/spring-beans/src/test/java/org/springframework/beans/factory/support/ManagedSetTests.java
@@ -25,61 +25,62 @@ import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException
 import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
+ * Unit tests for {@link ManagedSet}.
+ *
  * @author Rick Evans
  * @author Juergen Hoeller
  * @author Sam Brannen
  */
 @SuppressWarnings({ "rawtypes", "unchecked" })
-public class ManagedSetTests {
+class ManagedSetTests {
 
 	@Test
-	public void mergeSunnyDay() {
+	void mergeSunnyDay() {
 		ManagedSet parent = ManagedSet.of("one", "two");
 		ManagedSet child = ManagedSet.of("three");
 		child.add("three");
+		child.add("four");
 		child.setMergeEnabled(true);
 		Set mergedSet = child.merge(parent);
-		assertThat(mergedSet.size()).as("merge() obviously did not work.").isEqualTo(3);
+		assertThat(mergedSet).as("merge() obviously did not work.").containsExactly("one", "two", "three", "four");
 	}
 
 	@Test
-	public void mergeWithNullParent() {
+	void mergeWithNullParent() {
 		ManagedSet child = ManagedSet.of("one");
 		child.setMergeEnabled(true);
 		assertThat(child.merge(null)).isSameAs(child);
 	}
 
 	@Test
-	public void mergeNotAllowedWhenMergeNotEnabled() {
-		assertThatIllegalStateException().isThrownBy(() ->
-				new ManagedSet().merge(null));
+	void mergeNotAllowedWhenMergeNotEnabled() {
+		assertThatIllegalStateException().isThrownBy(() -> new ManagedSet().merge(null));
 	}
 
 	@Test
-	public void mergeWithNonCompatibleParentType() {
+	void mergeWithNonCompatibleParentType() {
 		ManagedSet child = ManagedSet.of("one");
 		child.setMergeEnabled(true);
-		assertThatIllegalArgumentException().isThrownBy(() ->
-				child.merge("hello"));
+		assertThatIllegalArgumentException().isThrownBy(() -> child.merge("hello"));
 	}
 
 	@Test
-	public void mergeEmptyChild() {
+	void mergeEmptyChild() {
 		ManagedSet parent = ManagedSet.of("one", "two");
 		ManagedSet child = new ManagedSet();
 		child.setMergeEnabled(true);
 		Set mergedSet = child.merge(parent);
-		assertThat(mergedSet.size()).as("merge() obviously did not work.").isEqualTo(2);
+		assertThat(mergedSet).as("merge() obviously did not work.").containsExactly("one", "two");
 	}
 
 	@Test
-	public void mergeChildValuesOverrideTheParents() {
+	void mergeChildValuesOverrideTheParents() {
 		// asserts that the set contract is not violated during a merge() operation...
 		ManagedSet parent = ManagedSet.of("one", "two");
 		ManagedSet child = ManagedSet.of("one");
 		child.setMergeEnabled(true);
 		Set mergedSet = child.merge(parent);
-		assertThat(mergedSet.size()).as("merge() obviously did not work.").isEqualTo(2);
+		assertThat(mergedSet).as("merge() obviously did not work.").containsExactly("one", "two");
 	}
 
 }