Stop using @ConditionalOnClass on @Bean methods

See gh-47429

Signed-off-by: Dmytro Nosan <dimanosan@gmail.com>

buildSrc/src/main/java/org/springframework/boot/build/architecture/ArchitectureCheck.java

@@ -70,15 +70,19 @@ import org.gradle.api.tasks.VerificationException;
  */
 public abstract class ArchitectureCheck extends DefaultTask {
 
+	private static final String CONDITIONAL_ON_CLASS_ANNOTATION = "org.springframework.boot.autoconfigure.condition.ConditionalOnClass";
+
 	private FileCollection classes;
 
 	public ArchitectureCheck() {
 		getOutputDirectory().convention(getProject().getLayout().getBuildDirectory().dir(getName()));
+		getConditionalOnClassAnnotation().convention(CONDITIONAL_ON_CLASS_ANNOTATION);
 		getRules().addAll(getProhibitObjectsRequireNonNull().convention(true)
 			.map(whenTrue(ArchitectureRules::noClassesShouldCallObjectsRequireNonNull)));
 		getRules().addAll(ArchitectureRules.standard());
-		getRules().addAll(whenMainSources(
-				() -> Collections.singletonList(ArchitectureRules.allBeanMethodsShouldReturnNonPrivateType())));
+		getRules().addAll(whenMainSources(() -> List
+			.of(ArchitectureRules.allBeanMethodsShouldReturnNonPrivateType(), ArchitectureRules
+				.allBeanMethodsShouldNotHaveConditionalOnClassAnnotation(getConditionalOnClassAnnotation().get()))));
 		getRuleDescriptions().set(getRules().map(this::asDescriptions));
 	}
 
@@ -186,4 +190,7 @@ public abstract class ArchitectureCheck extends DefaultTask {
 	@Input // Use descriptions as input since rules aren't serializable
 	abstract ListProperty<String> getRuleDescriptions();
 
+	@Internal
+	abstract Property<String> getConditionalOnClassAnnotation();
+
 }

buildSrc/src/main/java/org/springframework/boot/build/architecture/ArchitectureRules.java

@@ -108,6 +108,15 @@ final class ArchitectureRules {
 			.allowEmptyShould(true);
 	}
 
+	static ArchRule allBeanMethodsShouldNotHaveConditionalOnClassAnnotation(String annotationName) {
+		return methodsThatAreAnnotatedWith("org.springframework.context.annotation.Bean").should()
+			.notBeAnnotatedWith(annotationName)
+			.because("@ConditionalOnClass on @Bean methods is ineffective - it doesn't prevent "
+					+ "the method signature from being loaded. Such condition need to be placed"
+					+ " on a @Configuration class, allowing the condition to back off before the type is loaded.")
+			.allowEmptyShould(true);
+	}
+
 	private static ArchRule allPackagesShouldBeFreeOfTangles() {
 		return SlicesRuleDefinition.slices().matching("(**)").should().beFreeOfCycles();
 	}

buildSrc/src/test/java/org/springframework/boot/build/architecture/ArchitectureCheckTests.java

@@ -26,6 +26,7 @@ import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.UnaryOperator;
 
 import org.gradle.api.tasks.SourceSet;
 import org.gradle.testkit.runner.BuildResult;
@@ -39,6 +40,7 @@ import org.junit.jupiter.api.io.TempDir;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.EnumSource;
 
+import org.springframework.boot.build.architecture.annotations.TestConditionalOnClass;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.FileSystemUtils;
 import org.springframework.util.StringUtils;
@@ -180,7 +182,7 @@ class ArchitectureCheckTests {
 	void whenClassCallsObjectsRequireNonNullWithMessageAndProhibitObjectsRequireNonNullIsFalseShouldSucceedAndWriteEmptyReport(
 			Task task) throws IOException {
 		prepareTask(task, "objects/requireNonNullWithString");
-		build(this.gradleBuild.withProhibitObjectsRequireNonNull(task, false), task);
+		build(this.gradleBuild.withProhibitObjectsRequireNonNull(false), task);
 	}
 
 	@ParameterizedTest(name = "{0}")
@@ -195,7 +197,7 @@ class ArchitectureCheckTests {
 	void whenClassCallsObjectsRequireNonNullWithSupplierAndProhibitObjectsRequireNonNullIsFalseShouldSucceedAndWriteEmptyReport(
 			Task task) throws IOException {
 		prepareTask(task, "objects/requireNonNullWithSupplier");
-		build(this.gradleBuild.withProhibitObjectsRequireNonNull(task, false), task);
+		build(this.gradleBuild.withProhibitObjectsRequireNonNull(false), task);
 	}
 
 	@ParameterizedTest(name = "{0}")
@@ -295,6 +297,25 @@ class ArchitectureCheckTests {
 				"should not have a value that is the same as the type of the method's first parameter");
 	}
 
+	@Test
+	void whenConditionalOnClassUsedOnBeanMethodsWithMainSourcesShouldFailAndWriteReport() throws IOException {
+		prepareTask(Task.CHECK_ARCHITECTURE_MAIN, "conditionalonclass", "annotations");
+		GradleBuild gradleBuild = this.gradleBuild.withDependencies(SPRING_CONTEXT)
+			.withConditionalOnClassAnnotation(TestConditionalOnClass.class.getName());
+		buildAndFail(gradleBuild, Task.CHECK_ARCHITECTURE_MAIN,
+				"because @ConditionalOnClass on @Bean methods is ineffective - it doesn't prevent"
+						+ " the method signature from being loaded. Such condition need to be placed"
+						+ " on a @Configuration class, allowing the condition to back off before the type is loaded");
+	}
+
+	@Test
+	void whenConditionalOnClassUsedOnBeanMethodsWithTestSourcesShouldSucceedAndWriteEmptyReport() throws IOException {
+		prepareTask(Task.CHECK_ARCHITECTURE_TEST, "conditionalonclass", "annotations");
+		GradleBuild gradleBuild = this.gradleBuild.withDependencies(SPRING_CONTEXT)
+			.withConditionalOnClassAnnotation(TestConditionalOnClass.class.getName());
+		build(gradleBuild, Task.CHECK_ARCHITECTURE_TEST);
+	}
+
 	private void prepareTask(Task task, String... sourceDirectories) throws IOException {
 		for (String sourceDirectory : sourceDirectories) {
 			FileSystemUtils.copyRecursively(
@@ -310,7 +331,7 @@ class ArchitectureCheckTests {
 	private void build(GradleBuild gradleBuild, Task task) throws IOException {
 		try {
 			BuildResult buildResult = gradleBuild.build(task.toString());
-			assertThat(buildResult.taskPaths(TaskOutcome.SUCCESS)).contains(":" + task);
+			assertThat(buildResult.taskPaths(TaskOutcome.SUCCESS)).as(buildResult.getOutput()).contains(":" + task);
 			assertThat(task.getFailureReport(gradleBuild.getProjectDir())).isEmpty();
 		}
 		catch (UnexpectedBuildFailure ex) {
@@ -326,7 +347,7 @@ class ArchitectureCheckTests {
 	private void buildAndFail(GradleBuild gradleBuild, Task task, String... messages) throws IOException {
 		try {
 			BuildResult buildResult = gradleBuild.buildAndFail(task.toString());
-			assertThat(buildResult.taskPaths(TaskOutcome.FAILED)).contains(":" + task);
+			assertThat(buildResult.taskPaths(TaskOutcome.FAILED)).as(buildResult.getOutput()).contains(":" + task);
 			assertThat(task.getFailureReport(gradleBuild.getProjectDir())).contains(messages);
 		}
 		catch (UnexpectedBuildSuccess ex) {
@@ -371,7 +392,7 @@ class ArchitectureCheckTests {
 
 		private final Set<String> dependencies = new LinkedHashSet<>();
 
-		private final Map<Task, Boolean> prohibitObjectsRequireNonNull = new LinkedHashMap<>();
+		private final Map<Task, TaskConfiguration> taskConfigurations = new LinkedHashMap<>();
 
 		private GradleBuild(Path projectDir) {
 			this.projectDir = projectDir;
@@ -381,12 +402,28 @@ class ArchitectureCheckTests {
 			return this.projectDir;
 		}
 
-		GradleBuild withProhibitObjectsRequireNonNull(Task task, boolean prohibitObjectsRequireNonNull) {
-			this.prohibitObjectsRequireNonNull.put(task, prohibitObjectsRequireNonNull);
+		GradleBuild withProhibitObjectsRequireNonNull(Boolean prohibitObjectsRequireNonNull) {
+			for (Task task : Task.values()) {
+				configureTask(task, (configuration) -> configuration
+					.withProhibitObjectsRequireNonNull(prohibitObjectsRequireNonNull));
+			}
+			return this;
+		}
+
+		GradleBuild withConditionalOnClassAnnotation(String annotationName) {
+			for (Task task : Task.values()) {
+				configureTask(task, (configuration) -> configuration.withConditionalOnClassAnnotation(annotationName));
+			}
 			return this;
 		}
 
+		private void configureTask(Task task, UnaryOperator<TaskConfiguration> configurer) {
+			this.taskConfigurations.computeIfAbsent(task, (key) -> new TaskConfiguration(null, null));
+			this.taskConfigurations.compute(task, (key, value) -> configurer.apply(value));
+		}
+
 		GradleBuild withDependencies(String... dependencies) {
+			this.dependencies.clear();
 			this.dependencies.addAll(Arrays.asList(dependencies));
 			return this;
 		}
@@ -415,15 +452,22 @@ class ArchitectureCheckTests {
 			if (!this.dependencies.isEmpty()) {
 				buildFile.append("dependencies {\n");
 				for (String dependency : this.dependencies) {
-					buildFile.append("    implementation '%s'\n".formatted(dependency));
+					buildFile.append("\n    implementation ").append(StringUtils.quote(dependency));
 				}
 				buildFile.append("}\n");
 			}
-			this.prohibitObjectsRequireNonNull.forEach((task, prohibitObjectsRequireNonNull) -> buildFile.append(task)
-				.append(" {\n")
-				.append("    prohibitObjectsRequireNonNull = ")
-				.append(prohibitObjectsRequireNonNull)
-				.append("\n}\n\n"));
+			this.taskConfigurations.forEach((task, configuration) -> {
+				buildFile.append(task).append(" {");
+				if (configuration.conditionalOnClassAnnotation() != null) {
+					buildFile.append("\n    conditionalOnClassAnnotation = ")
+						.append(StringUtils.quote(configuration.conditionalOnClassAnnotation()));
+				}
+				if (configuration.prohibitObjectsRequireNonNull() != null) {
+					buildFile.append("\n    prohibitObjectsRequireNonNull = ")
+						.append(configuration.prohibitObjectsRequireNonNull());
+				}
+				buildFile.append("\n}\n");
+			});
 			Files.writeString(this.projectDir.resolve("build.gradle"), buildFile, StandardCharsets.UTF_8);
 			return GradleRunner.create()
 				.withProjectDir(this.projectDir.toFile())
@@ -431,6 +475,17 @@ class ArchitectureCheckTests {
 				.withPluginClasspath();
 		}
 
+		private record TaskConfiguration(Boolean prohibitObjectsRequireNonNull, String conditionalOnClassAnnotation) {
+
+			private TaskConfiguration withConditionalOnClassAnnotation(String annotationName) {
+				return new TaskConfiguration(this.prohibitObjectsRequireNonNull, annotationName);
+			}
+
+			private TaskConfiguration withProhibitObjectsRequireNonNull(Boolean prohibitObjectsRequireNonNull) {
+				return new TaskConfiguration(prohibitObjectsRequireNonNull, this.conditionalOnClassAnnotation);
+			}
+		}
+
 	}
 
 }

buildSrc/src/test/java/org/springframework/boot/build/architecture/annotations/TestConditionalOnClass.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2012-present 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.build.architecture.annotations;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * {@code @ConditionalOnClass} analogue for architecture checks.
+ *
+ */
+@Target({ ElementType.TYPE, ElementType.METHOD })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface TestConditionalOnClass {
+
+	Class<?>[] value() default {};
+
+	String[] name() default {};
+
+}

buildSrc/src/test/java/org/springframework/boot/build/architecture/conditionalonclass/OnBeanMethod.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2012-present 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.build.architecture.conditionalonclass;
+
+import org.springframework.boot.build.architecture.annotations.TestConditionalOnClass;
+import org.springframework.context.annotation.Bean;
+
+class OnBeanMethod {
+
+	@Bean
+	@TestConditionalOnClass(String.class)
+	String helloWorld() {
+		return "Hello World";
+	}
+
+}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/audit/AuditAutoConfiguration.java

@@ -31,6 +31,7 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
 
 /**
  * {@link EnableAutoConfiguration Auto-configuration} for {@link AuditEvent}s.
@@ -50,18 +51,28 @@ public class AuditAutoConfiguration {
 		return new AuditListener(auditEventRepository);
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "org.springframework.security.authentication.event.AbstractAuthenticationEvent")
-	@ConditionalOnMissingBean(AbstractAuthenticationAuditListener.class)
-	public AuthenticationAuditListener authenticationAuditListener() {
-		return new AuthenticationAuditListener();
+	static class AuthenticationAuditConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean(AbstractAuthenticationAuditListener.class)
+		AuthenticationAuditListener authenticationAuditListener() {
+			return new AuthenticationAuditListener();
+		}
+
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "org.springframework.security.access.event.AbstractAuthorizationEvent")
-	@ConditionalOnMissingBean(AbstractAuthorizationAuditListener.class)
-	public AuthorizationAuditListener authorizationAuditListener() {
-		return new AuthorizationAuditListener();
+	static class AuthorizationAuditConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean(AbstractAuthorizationAuditListener.class)
+		AuthorizationAuditListener authorizationAuditListener() {
+			return new AuthorizationAuditListener();
+		}
+
 	}
 
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/endpoint/jackson/JacksonEndpointAutoConfiguration.java

@@ -36,12 +36,12 @@ import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
  * @since 3.0.0
  */
 @AutoConfiguration(after = JacksonAutoConfiguration.class)
+@ConditionalOnClass({ ObjectMapper.class, Jackson2ObjectMapperBuilder.class })
 public class JacksonEndpointAutoConfiguration {
 
 	@Bean
 	@ConditionalOnProperty(name = "management.endpoints.jackson.isolated-object-mapper", matchIfMissing = true)
-	@ConditionalOnClass({ ObjectMapper.class, Jackson2ObjectMapperBuilder.class })
-	public EndpointObjectMapper endpointObjectMapper() {
+	EndpointObjectMapper endpointObjectMapper() {
 		ObjectMapper objectMapper = Jackson2ObjectMapperBuilder.json()
 			.featuresToDisable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS,
 					SerializationFeature.WRITE_DURATIONS_AS_TIMESTAMPS)

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/security/servlet/SecurityRequestMatchersManagementContextConfiguration.java

@@ -53,7 +53,6 @@ public class SecurityRequestMatchersManagementContextConfiguration {
 
 		@Bean
 		@ConditionalOnMissingBean
-		@ConditionalOnClass(DispatcherServlet.class)
 		public RequestMatcherProvider requestMatcherProvider(DispatcherServletPath servletPath) {
 			return new AntPathRequestMatcherProvider(servletPath::getRelativePath);
 		}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/servlet/ServletManagementChildContextConfiguration.java

@@ -81,22 +81,37 @@ class ServletManagementChildContextConfiguration {
 		return new ServletManagementWebServerFactoryCustomizer(beanFactory);
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "io.undertow.Undertow")
-	UndertowAccessLogCustomizer undertowManagementAccessLogCustomizer() {
-		return new UndertowAccessLogCustomizer();
+	static class UndertowConfiguration {
+
+		@Bean
+		UndertowAccessLogCustomizer undertowManagementAccessLogCustomizer() {
+			return new UndertowAccessLogCustomizer();
+		}
+
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "org.apache.catalina.valves.AccessLogValve")
-	TomcatAccessLogCustomizer tomcatManagementAccessLogCustomizer() {
-		return new TomcatAccessLogCustomizer();
+	static class TomcatConfiguration {
+
+		@Bean
+		TomcatAccessLogCustomizer tomcatManagementAccessLogCustomizer() {
+			return new TomcatAccessLogCustomizer();
+		}
+
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "org.eclipse.jetty.server.Server")
-	JettyAccessLogCustomizer jettyManagementAccessLogCustomizer() {
-		return new JettyAccessLogCustomizer();
+	static class JettyConfiguration {
+
+		@Bean
+		JettyAccessLogCustomizer jettyManagementAccessLogCustomizer() {
+			return new JettyAccessLogCustomizer();
+		}
+
 	}
 
 	@Configuration(proxyBeanMethods = false)

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration.java

@@ -144,24 +144,6 @@ public class FlywayAutoConfiguration {
 			return new PropertiesFlywayConnectionDetails(this.properties);
 		}
 
-		@Bean
-		@ConditionalOnClass(name = "org.flywaydb.database.sqlserver.SQLServerConfigurationExtension")
-		SqlServerFlywayConfigurationCustomizer sqlServerFlywayConfigurationCustomizer() {
-			return new SqlServerFlywayConfigurationCustomizer(this.properties);
-		}
-
-		@Bean
-		@ConditionalOnClass(name = "org.flywaydb.database.oracle.OracleConfigurationExtension")
-		OracleFlywayConfigurationCustomizer oracleFlywayConfigurationCustomizer() {
-			return new OracleFlywayConfigurationCustomizer(this.properties);
-		}
-
-		@Bean
-		@ConditionalOnClass(name = "org.flywaydb.database.postgresql.PostgreSQLConfigurationExtension")
-		PostgresqlFlywayConfigurationCustomizer postgresqlFlywayConfigurationCustomizer() {
-			return new PostgresqlFlywayConfigurationCustomizer(this.properties);
-		}
-
 		@Bean
 		Flyway flyway(FlywayConnectionDetails connectionDetails, ResourceLoader resourceLoader,
 				ObjectProvider<DataSource> dataSource, @FlywayDataSource ObjectProvider<DataSource> flywayDataSource,
@@ -355,6 +337,40 @@ public class FlywayAutoConfiguration {
 			return new FlywayMigrationInitializer(flyway, migrationStrategy.getIfAvailable());
 		}
 
+		@ConditionalOnClass(name = "org.flywaydb.database.sqlserver.SQLServerConfigurationExtension")
+		@Configuration(proxyBeanMethods = false)
+		static class SqlServerConfiguration {
+
+			@Bean
+			SqlServerFlywayConfigurationCustomizer sqlServerFlywayConfigurationCustomizer(FlywayProperties properties) {
+				return new SqlServerFlywayConfigurationCustomizer(properties);
+			}
+
+		}
+
+		@Configuration(proxyBeanMethods = false)
+		@ConditionalOnClass(name = "org.flywaydb.database.oracle.OracleConfigurationExtension")
+		static class OracleConfiguration {
+
+			@Bean
+			OracleFlywayConfigurationCustomizer oracleFlywayConfigurationCustomizer(FlywayProperties properties) {
+				return new OracleFlywayConfigurationCustomizer(properties);
+			}
+
+		}
+
+		@ConditionalOnClass(name = "org.flywaydb.database.postgresql.PostgreSQLConfigurationExtension")
+		@Configuration(proxyBeanMethods = false)
+		static class PostgresqlConfiguration {
+
+			@Bean
+			PostgresqlFlywayConfigurationCustomizer postgresqlFlywayConfigurationCustomizer(
+					FlywayProperties properties) {
+				return new PostgresqlFlywayConfigurationCustomizer(properties);
+			}
+
+		}
+
 	}
 
 	private static class LocationResolver {

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/hateoas/HypermediaAutoConfiguration.java

@@ -57,13 +57,18 @@ import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandl
 @EnableConfigurationProperties(HateoasProperties.class)
 public class HypermediaAutoConfiguration {
 
-	@Bean
-	@ConditionalOnMissingBean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "com.fasterxml.jackson.databind.ObjectMapper")
 	@ConditionalOnProperty(prefix = "spring.hateoas", name = "use-hal-as-default-json-media-type",
 			matchIfMissing = true)
-	HalConfiguration applicationJsonHalConfiguration() {
-		return new HalConfiguration().withMediaType(MediaType.APPLICATION_JSON);
+	static class JacksonJsonHalConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		HalConfiguration applicationJsonHalConfiguration() {
+			return new HalConfiguration().withMediaType(MediaType.APPLICATION_JSON);
+		}
+
 	}
 
 	@Configuration(proxyBeanMethods = false)

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/pulsar/PulsarReactiveAutoConfiguration.java

@@ -87,16 +87,6 @@ public class PulsarReactiveAutoConfiguration {
 		return AdaptedReactivePulsarClientFactory.create(pulsarClient);
 	}
 
-	@Bean
-	@ConditionalOnMissingBean(ProducerCacheProvider.class)
-	@ConditionalOnClass(CaffeineShadedProducerCacheProvider.class)
-	@ConditionalOnProperty(name = "spring.pulsar.producer.cache.enabled", havingValue = "true", matchIfMissing = true)
-	CaffeineShadedProducerCacheProvider reactivePulsarProducerCacheProvider() {
-		PulsarProperties.Producer.Cache properties = this.properties.getProducer().getCache();
-		return new CaffeineShadedProducerCacheProvider(properties.getExpireAfterAccess(), Duration.ofMinutes(10),
-				properties.getMaximumSize(), properties.getInitialCapacity());
-	}
-
 	@Bean
 	@ConditionalOnMissingBean
 	@ConditionalOnProperty(name = "spring.pulsar.producer.cache.enabled", havingValue = "true", matchIfMissing = true)
@@ -205,6 +195,21 @@ public class PulsarReactiveAutoConfiguration {
 		return new ReactivePulsarTemplate<>(reactivePulsarSenderFactory, schemaResolver, topicResolver);
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	@ConditionalOnClass(CaffeineShadedProducerCacheProvider.class)
+	@ConditionalOnProperty(name = "spring.pulsar.producer.cache.enabled", havingValue = "true", matchIfMissing = true)
+	static class PulsarCacheConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean(ProducerCacheProvider.class)
+		CaffeineShadedProducerCacheProvider reactivePulsarProducerCacheProvider(PulsarProperties pulsarProperties) {
+			PulsarProperties.Producer.Cache properties = pulsarProperties.getProducer().getCache();
+			return new CaffeineShadedProducerCacheProvider(properties.getExpireAfterAccess(), Duration.ofMinutes(10),
+					properties.getMaximumSize(), properties.getInitialCapacity());
+		}
+
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	@EnableReactivePulsar
 	@ConditionalOnMissingBean(

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/reactive/ReactiveWebServerFactoryAutoConfiguration.java

@@ -36,6 +36,7 @@ import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.boot.ssl.SslBundles;
 import org.springframework.boot.web.server.WebServerFactoryCustomizerBeanPostProcessor;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
 import org.springframework.core.Ordered;
@@ -69,13 +70,6 @@ public class ReactiveWebServerFactoryAutoConfiguration {
 		return new ReactiveWebServerFactoryCustomizer(serverProperties, sslBundles.getIfAvailable());
 	}
 
-	@Bean
-	@ConditionalOnClass(name = "org.apache.catalina.startup.Tomcat")
-	public TomcatReactiveWebServerFactoryCustomizer tomcatReactiveWebServerFactoryCustomizer(
-			ServerProperties serverProperties) {
-		return new TomcatReactiveWebServerFactoryCustomizer(serverProperties);
-	}
-
 	@Bean
 	@ConditionalOnMissingBean
 	@ConditionalOnProperty(value = "server.forward-headers-strategy", havingValue = "framework")
@@ -83,6 +77,18 @@ public class ReactiveWebServerFactoryAutoConfiguration {
 		return new ForwardedHeaderTransformer();
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	@ConditionalOnClass(name = "org.apache.catalina.startup.Tomcat")
+	static class TomcatConfiguration {
+
+		@Bean
+		TomcatReactiveWebServerFactoryCustomizer tomcatReactiveWebServerFactoryCustomizer(
+				ServerProperties serverProperties) {
+			return new TomcatReactiveWebServerFactoryCustomizer(serverProperties);
+		}
+
+	}
+
 	/**
 	 * Registers a {@link WebServerFactoryCustomizerBeanPostProcessor}. Registered via
 	 * {@link ImportBeanDefinitionRegistrar} for early registration.

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/ServletWebServerFactoryAutoConfiguration.java

@@ -81,11 +81,16 @@ public class ServletWebServerFactoryAutoConfiguration {
 				cookieSameSiteSuppliers.orderedStream().toList(), sslBundles.getIfAvailable());
 	}
 
-	@Bean
+	@Configuration(proxyBeanMethods = false)
 	@ConditionalOnClass(name = "org.apache.catalina.startup.Tomcat")
-	public TomcatServletWebServerFactoryCustomizer tomcatServletWebServerFactoryCustomizer(
-			ServerProperties serverProperties) {
-		return new TomcatServletWebServerFactoryCustomizer(serverProperties);
+	static class TomcatConfiguration {
+
+		@Bean
+		TomcatServletWebServerFactoryCustomizer tomcatServletWebServerFactoryCustomizer(
+				ServerProperties serverProperties) {
+			return new TomcatServletWebServerFactoryCustomizer(serverProperties);
+		}
+
 	}
 
 	@Configuration(proxyBeanMethods = false)
@@ -93,12 +98,6 @@ public class ServletWebServerFactoryAutoConfiguration {
 	@ConditionalOnMissingFilterBean(ForwardedHeaderFilter.class)
 	static class ForwardedHeaderFilterConfiguration {
 
-		@Bean
-		@ConditionalOnClass(name = "org.apache.catalina.startup.Tomcat")
-		ForwardedHeaderFilterCustomizer tomcatForwardedHeaderFilterCustomizer(ServerProperties serverProperties) {
-			return (filter) -> filter.setRelativeRedirects(serverProperties.getTomcat().isUseRelativeRedirects());
-		}
-
 		@Bean
 		FilterRegistrationBean<ForwardedHeaderFilter> forwardedHeaderFilter(
 				ObjectProvider<ForwardedHeaderFilterCustomizer> customizerProvider) {
@@ -110,6 +109,17 @@ public class ServletWebServerFactoryAutoConfiguration {
 			return registration;
 		}
 
+		@Configuration(proxyBeanMethods = false)
+		@ConditionalOnClass(name = "org.apache.catalina.startup.Tomcat")
+		static class TomcatConfiguration {
+
+			@Bean
+			ForwardedHeaderFilterCustomizer tomcatForwardedHeaderFilterCustomizer(ServerProperties serverProperties) {
+				return (filter) -> filter.setRelativeRedirects(serverProperties.getTomcat().isUseRelativeRedirects());
+			}
+
+		}
+
 	}
 
 	interface ForwardedHeaderFilterCustomizer {