diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/annotation/ImportCandidates.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/annotation/ImportCandidates.java
index efecb9bfc2..3db5cc44a7 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/annotation/ImportCandidates.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/annotation/ImportCandidates.java
@@ -27,8 +27,6 @@ import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.List;
 
-import org.jetbrains.annotations.NotNull;
-
 import org.springframework.core.io.UrlResource;
 import org.springframework.util.Assert;
 
@@ -54,7 +52,6 @@ public final class ImportCandidates implements Iterable<String> {
 		this.candidates = Collections.unmodifiableList(candidates);
 	}
 
-	@NotNull
 	@Override
 	public Iterator<String> iterator() {
 		return this.candidates.iterator();
diff --git a/src/checkstyle/checkstyle.xml b/src/checkstyle/checkstyle.xml
index f0f1aa09ee..e55f14aec6 100644
--- a/src/checkstyle/checkstyle.xml
+++ b/src/checkstyle/checkstyle.xml
@@ -13,7 +13,8 @@
 			name="com.puppycrawl.tools.checkstyle.checks.imports.IllegalImportCheck">
 			<property name="regexp" value="true" />
 			<property name="illegalPkgs"
-				value="^sun.*, ^org\.apache\.commons\.(?!compress|dbcp2|logging|pool2).*, ^com\.datastax\.oss\.driver\.shaded.*, ^com\.google\.common.*, ^io\.micrometer\.shaded.*, ^org\.testcontainers\.shaded.*" />
+				value="^sun.*, ^org\.apache\.commons\.(?!compress|dbcp2|logging|pool2).*, ^com\.datastax\.oss\.driver\.shaded.*, ^com\.google\.common.*, ^io\.micrometer\.shaded.*,
+				 ^org\.jetbrains\.annotations.*, ^org\.testcontainers\.shaded.*" />
 			<property name="illegalClasses"
 				value="^com\.hazelcast\.util\.Base64, ^org\.junit\.rules\.ExpectedException, ^org\.mockito\.InjectMocks, ^org\.slf4j\.LoggerFactory, ^org.springframework.context.annotation.ScannedGenericBeanDefinition, ^reactor\.core\.support\.Assert"/>
 		</module>
diff --git a/src/checkstyle/import-control.xml b/src/checkstyle/import-control.xml
index 936300d8b5..397dc03fb6 100644
--- a/src/checkstyle/import-control.xml
+++ b/src/checkstyle/import-control.xml
@@ -2,6 +2,7 @@
 <!DOCTYPE import-control PUBLIC "-//Checkstyle//DTD ImportControl Configuration 1.4//EN" "https://checkstyle.org/dtds/import_control_1_4.dtd">
 <import-control pkg="org.springframework.boot">
 	<disallow pkg="io.micrometer" />
+	<disallow pkg="org.springframework.lang" />
 	<allow pkg=".*" regex="true" />
 	<subpackage name="autoconfigure">
 		<disallow class="org.springframework.boot.autoconfigure.jdbc.DataSourceProperties"/>
@@ -45,6 +46,13 @@
 		<subpackage name="endpoint">
 			<disallow pkg="org.springframework.http" />
 			<disallow pkg="org.springframework.web" />
+			<subpackage name="invoke">
+				<subpackage name="reflect">
+					<file name="OperationMethodParameter">
+						<allow pkg="org.springframework.lang"/>
+					</file>
+				</subpackage>
+			</subpackage>
 			<subpackage name="web">
 				<allow pkg="org.springframework.http" />
 				<allow pkg="org.springframework.web" />
@@ -56,6 +64,9 @@
 				</subpackage>
 			</subpackage>
 		</subpackage>
+		<file name=".*Endpoint(WebExtension)?" regex="true">
+			<allow pkg="org.springframework.lang"/>
+		</file>
 	</subpackage>
 
 	<subpackage name="docs">