diff --git a/spring-core/src/main/java/org/springframework/util/ClassUtils.java b/spring-core/src/main/java/org/springframework/util/ClassUtils.java
index 11197d2b55..d0c83bd92d 100644
--- a/spring-core/src/main/java/org/springframework/util/ClassUtils.java
+++ b/spring-core/src/main/java/org/springframework/util/ClassUtils.java
@@ -121,6 +121,7 @@ public abstract class ClassUtils {
 		primitiveWrapperTypeMap.put(Integer.class, int.class);
 		primitiveWrapperTypeMap.put(Long.class, long.class);
 		primitiveWrapperTypeMap.put(Short.class, short.class);
+		primitiveWrapperTypeMap.put(Void.class, void.class);
 
 		// Map entry iteration is less expensive to initialize than forEach with lambdas
 		for (Map.Entry<Class<?>, Class<?>> entry : primitiveWrapperTypeMap.entrySet()) {
@@ -463,7 +464,8 @@ public abstract class ClassUtils {
 
 	/**
 	 * Check if the given class represents a primitive wrapper,
-	 * i.e. Boolean, Byte, Character, Short, Integer, Long, Float, or Double.
+	 * i.e. Boolean, Byte, Character, Short, Integer, Long, Float, Double, or
+	 * Void.
 	 * @param clazz the class to check
 	 * @return whether the given class is a primitive wrapper class
 	 */
@@ -474,10 +476,12 @@ public abstract class ClassUtils {
 
 	/**
 	 * Check if the given class represents a primitive (i.e. boolean, byte,
-	 * char, short, int, long, float, or double) or a primitive wrapper
-	 * (i.e. Boolean, Byte, Character, Short, Integer, Long, Float, or Double).
+	 * char, short, int, long, float, or double), {@code void}, or a wrapper for
+	 * those types (i.e. Boolean, Byte, Character, Short, Integer, Long, Float,
+	 * Double, or Void).
 	 * @param clazz the class to check
-	 * @return whether the given class is a primitive or primitive wrapper class
+	 * @return {@code true} if the given class represents a primitive, void, or
+	 * a wrapper class
 	 */
 	public static boolean isPrimitiveOrWrapper(Class<?> clazz) {
 		Assert.notNull(clazz, "Class must not be null");
diff --git a/spring-core/src/test/java/org/springframework/util/ClassUtilsTests.java b/spring-core/src/test/java/org/springframework/util/ClassUtilsTests.java
index 2b58da23b6..709c7bace1 100644
--- a/spring-core/src/test/java/org/springframework/util/ClassUtilsTests.java
+++ b/spring-core/src/test/java/org/springframework/util/ClassUtilsTests.java
@@ -40,14 +40,17 @@ import org.springframework.tests.sample.objects.TestObject;
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
+ * Unit tests for {@link ClassUtils}.
+ *
  * @author Colin Sampaleanu
  * @author Juergen Hoeller
  * @author Rob Harrop
  * @author Rick Evans
+ * @author Sam Brannen
  */
 class ClassUtilsTests {
 
-	private ClassLoader classLoader = getClass().getClassLoader();
+	private final ClassLoader classLoader = getClass().getClassLoader();
 
 
 	@BeforeEach
@@ -380,6 +383,42 @@ class ClassUtilsTests {
 		assertThat(ClassUtils.determineCommonAncestor(String.class, List.class)).isNull();
 	}
 
+	@Test
+	public void isPrimitiveWrapper() {
+		assertThat(ClassUtils.isPrimitiveWrapper(Boolean.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Character.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Byte.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Short.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Integer.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Long.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Float.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Double.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveWrapper(Void.class)).isTrue();
+	}
+
+	@Test
+	public void isPrimitiveOrWrapper() {
+		assertThat(ClassUtils.isPrimitiveOrWrapper(boolean.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(char.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(byte.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(short.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(int.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(long.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(float.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(double.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(void.class)).isTrue();
+
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Boolean.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Character.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Byte.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Short.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Integer.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Long.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Float.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Double.class)).isTrue();
+		assertThat(ClassUtils.isPrimitiveOrWrapper(Void.class)).isTrue();
+	}
+
 
 	public static class InnerClass {
 
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandler.java b/spring-webflux/src/main/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandler.java
index 691fac712b..66637a2ac8 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandler.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandler.java
@@ -162,7 +162,7 @@ public class ViewResolutionResultHandler extends HandlerResultHandlerSupport
 
 		return (CharSequence.class.isAssignableFrom(type) || Rendering.class.isAssignableFrom(type) ||
 				Model.class.isAssignableFrom(type) || Map.class.isAssignableFrom(type) ||
-				void.class.equals(type) || View.class.isAssignableFrom(type) ||
+				Void.class.equals(type) || void.class.equals(type) || View.class.isAssignableFrom(type) ||
 				!BeanUtils.isSimpleProperty(type));
 	}
 
diff --git a/spring-webflux/src/test/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandlerTests.java b/spring-webflux/src/test/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandlerTests.java
index 8e5cd2ef01..386ed8b30b 100644
--- a/spring-webflux/src/test/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandlerTests.java
+++ b/spring-webflux/src/test/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandlerTests.java
@@ -114,7 +114,12 @@ public class ViewResolutionResultHandlerTests {
 	private void testSupports(MethodParameter returnType, boolean supports) {
 		ViewResolutionResultHandler resultHandler = resultHandler(mock(ViewResolver.class));
 		HandlerResult handlerResult = new HandlerResult(new Object(), null, returnType, this.bindingContext);
-		assertThat(resultHandler.supports(handlerResult)).isEqualTo(supports);
+		if (supports) {
+			assertThat(resultHandler.supports(handlerResult)).as("return type [" + returnType + "] should be supported").isEqualTo(supports);
+		}
+		else {
+			assertThat(resultHandler.supports(handlerResult)).as("return type [" + returnType + "] should not be supported").isNotEqualTo(supports);
+		}
 	}
 
 	@Test