Merge branch '3.3.x' into 3.4.x

Closes gh-44697

buildSrc/src/main/java/org/springframework/boot/build/ConventionsPlugin.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -50,6 +50,7 @@ public class ConventionsPlugin implements Plugin<Project> {
 		new KotlinConventions().apply(project);
 		new WarConventions().apply(project);
 		new EclipseConventions().apply(project);
+		new TestFixturesConventions().apply(project);
 		RepositoryTransformersExtension.apply(project);
 	}
 

buildSrc/src/main/java/org/springframework/boot/build/TestFixturesConventions.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2012-2025 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.
+ * 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;
+
+import org.gradle.api.Project;
+import org.gradle.api.artifacts.ConfigurationContainer;
+import org.gradle.api.component.AdhocComponentWithVariants;
+import org.gradle.api.plugins.JavaTestFixturesPlugin;
+
+/**
+ * Conventions that are applied in the presence of the {@link JavaTestFixturesPlugin}.
+ * When the plugin is applied:
+ *
+ * <ul>
+ * <li>Publishing of the test fixtures is disabled.
+ * </ul>
+ *
+ * @author Andy Wilkinson
+ */
+class TestFixturesConventions {
+
+	void apply(Project project) {
+		project.getPlugins().withType(JavaTestFixturesPlugin.class, (testFixtures) -> disablePublishing(project));
+	}
+
+	private void disablePublishing(Project project) {
+		ConfigurationContainer configurations = project.getConfigurations();
+		AdhocComponentWithVariants javaComponent = (AdhocComponentWithVariants) project.getComponents()
+			.getByName("java");
+		javaComponent.withVariantsFromConfiguration(configurations.getByName("testFixturesApiElements"),
+				(variant) -> variant.skip());
+		javaComponent.withVariantsFromConfiguration(configurations.getByName("testFixturesRuntimeElements"),
+				(variant) -> variant.skip());
+	}
+
+}

spring-boot-project/spring-boot-actuator-autoconfigure/build.gradle

@@ -137,6 +137,7 @@ dependencies {
 
 	testImplementation(project(":spring-boot-project:spring-boot-test"))
 	testImplementation(project(":spring-boot-project:spring-boot-tools:spring-boot-test-support"))
+	testImplementation(testFixtures(project(":spring-boot-project:spring-boot")))
 	testImplementation("io.micrometer:micrometer-observation-test")
 	testImplementation("io.projectreactor:reactor-test")
 	testImplementation("io.prometheus:prometheus-metrics-exposition-formats")

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/web/servlet/MockServletWebServerFactory.java

@@ -1,79 +0,0 @@
-/*
- * Copyright 2012-2023 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.actuate.autoconfigure.web.servlet;
-
-import java.util.Arrays;
-
-import jakarta.servlet.ServletContext;
-
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredFilter;
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredServlet;
-import org.springframework.boot.web.server.WebServer;
-import org.springframework.boot.web.servlet.ServletContextInitializer;
-import org.springframework.boot.web.servlet.server.AbstractServletWebServerFactory;
-import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
-
-import static org.mockito.Mockito.spy;
-
-/**
- * Mock {@link ServletWebServerFactory}.
- *
- * @author Phillip Webb
- * @author Andy Wilkinson
- */
-public class MockServletWebServerFactory extends AbstractServletWebServerFactory {
-
-	private MockServletWebServer webServer;
-
-	@Override
-	public WebServer getWebServer(ServletContextInitializer... initializers) {
-		this.webServer = spy(new MockServletWebServer(mergeInitializers(initializers), getPort()));
-		return this.webServer;
-	}
-
-	public MockServletWebServer getWebServer() {
-		return this.webServer;
-	}
-
-	public ServletContext getServletContext() {
-		return (getWebServer() != null) ? getWebServer().getServletContext() : null;
-	}
-
-	public RegisteredServlet getRegisteredServlet(int index) {
-		return (getWebServer() != null) ? getWebServer().getRegisteredServlet(index) : null;
-	}
-
-	public RegisteredFilter getRegisteredFilter(int index) {
-		return (getWebServer() != null) ? getWebServer().getRegisteredFilters(index) : null;
-	}
-
-	static class MockServletWebServer extends org.springframework.boot.testsupport.web.servlet.MockServletWebServer
-			implements WebServer {
-
-		MockServletWebServer(ServletContextInitializer[] initializers, int port) {
-			super(Arrays.stream(initializers)
-				.map((initializer) -> (Initializer) initializer::onStartup)
-				.toArray(Initializer[]::new), port);
-		}
-
-		@Override
-		public void start() {
-		}
-
-	}
-
-}

spring-boot-project/spring-boot-autoconfigure/build.gradle

@@ -24,6 +24,7 @@ dependencies {
 
 	dockerTestImplementation(project(":spring-boot-project:spring-boot-test"))
 	dockerTestImplementation(project(":spring-boot-project:spring-boot-tools:spring-boot-test-support-docker"))
+	dockerTestImplementation(testFixtures(project(":spring-boot-project:spring-boot")))
 	dockerTestImplementation("com.redis:testcontainers-redis")
 	dockerTestImplementation("org.assertj:assertj-core")
 	dockerTestImplementation("org.awaitility:awaitility")
@@ -234,6 +235,7 @@ dependencies {
 
 	testImplementation(project(":spring-boot-project:spring-boot-tools:spring-boot-test-support"))
 	testImplementation(project(":spring-boot-project:spring-boot-test"))
+	testImplementation(testFixtures(project(":spring-boot-project:spring-boot")))
 	testImplementation("ch.qos.logback:logback-classic")
 	testImplementation("commons-fileupload:commons-fileupload")
 	testImplementation("com.github.h-thurow:simple-jndi")

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnNotWebApplicationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -19,10 +19,10 @@ package org.springframework.boot.autoconfigure.condition;
 import org.junit.jupiter.api.Test;
 import reactor.core.publisher.Mono;
 
-import org.springframework.boot.autoconfigure.web.reactive.MockReactiveWebServerFactory;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
 import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
+import org.springframework.boot.web.reactive.server.MockReactiveWebServerFactory;
 import org.springframework.boot.web.reactive.server.ReactiveWebServerFactory;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnWebApplicationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -21,8 +21,8 @@ import org.junit.jupiter.api.Test;
 import reactor.core.publisher.Mono;
 
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
-import org.springframework.boot.autoconfigure.web.reactive.MockReactiveWebServerFactory;
 import org.springframework.boot.web.reactive.context.AnnotationConfigReactiveWebApplicationContext;
+import org.springframework.boot.web.reactive.server.MockReactiveWebServerFactory;
 import org.springframework.boot.web.reactive.server.ReactiveWebServerFactory;
 import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebApplicationContext;
 import org.springframework.context.ConfigurableApplicationContext;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/session/AbstractSessionAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -19,11 +19,11 @@ package org.springframework.boot.autoconfigure.session;
 import java.util.Collections;
 import java.util.function.Consumer;
 
-import org.springframework.boot.autoconfigure.web.reactive.MockReactiveWebServerFactory;
 import org.springframework.boot.test.context.assertj.AssertableReactiveWebApplicationContext;
 import org.springframework.boot.test.context.assertj.AssertableWebApplicationContext;
 import org.springframework.boot.test.context.runner.ContextConsumer;
 import org.springframework.boot.web.reactive.context.ReactiveWebApplicationContext;
+import org.springframework.boot.web.reactive.server.MockReactiveWebServerFactory;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.mock.http.server.reactive.MockServerHttpRequest;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/reactive/MockReactiveWebServerFactory.java

@@ -1,90 +0,0 @@
-/*
- * Copyright 2012-2021 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.autoconfigure.web.reactive;
-
-import java.util.Map;
-
-import org.springframework.boot.web.reactive.server.AbstractReactiveWebServerFactory;
-import org.springframework.boot.web.reactive.server.ReactiveWebServerFactory;
-import org.springframework.boot.web.server.WebServer;
-import org.springframework.http.server.reactive.HttpHandler;
-
-import static org.mockito.Mockito.spy;
-
-/**
- * Mock {@link ReactiveWebServerFactory}.
- *
- * @author Brian Clozel
- */
-public class MockReactiveWebServerFactory extends AbstractReactiveWebServerFactory {
-
-	private MockReactiveWebServer webServer;
-
-	@Override
-	public WebServer getWebServer(HttpHandler httpHandler) {
-		this.webServer = spy(new MockReactiveWebServer(httpHandler, getPort()));
-		return this.webServer;
-	}
-
-	public MockReactiveWebServer getWebServer() {
-		return this.webServer;
-	}
-
-	static class MockReactiveWebServer implements WebServer {
-
-		private final int port;
-
-		private HttpHandler httpHandler;
-
-		private Map<String, HttpHandler> httpHandlerMap;
-
-		MockReactiveWebServer(HttpHandler httpHandler, int port) {
-			this.httpHandler = httpHandler;
-			this.port = port;
-		}
-
-		MockReactiveWebServer(Map<String, HttpHandler> httpHandlerMap, int port) {
-			this.httpHandlerMap = httpHandlerMap;
-			this.port = port;
-		}
-
-		HttpHandler getHttpHandler() {
-			return this.httpHandler;
-		}
-
-		Map<String, HttpHandler> getHttpHandlerMap() {
-			return this.httpHandlerMap;
-		}
-
-		@Override
-		public void start() {
-
-		}
-
-		@Override
-		public void stop() {
-
-		}
-
-		@Override
-		public int getPort() {
-			return this.port;
-		}
-
-	}
-
-}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/reactive/ReactiveWebServerFactoryAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -45,6 +45,7 @@ import org.springframework.boot.web.embedded.undertow.UndertowReactiveWebServerF
 import org.springframework.boot.web.reactive.context.AnnotationConfigReactiveWebApplicationContext;
 import org.springframework.boot.web.reactive.context.AnnotationConfigReactiveWebServerApplicationContext;
 import org.springframework.boot.web.reactive.server.ConfigurableReactiveWebServerFactory;
+import org.springframework.boot.web.reactive.server.MockReactiveWebServerFactory;
 import org.springframework.boot.web.reactive.server.ReactiveWebServerFactory;
 import org.springframework.boot.web.server.WebServerFactoryCustomizer;
 import org.springframework.context.ApplicationContextException;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/reactive/WebFluxAutoConfigurationTests.java

@@ -61,6 +61,7 @@ import org.springframework.boot.testsupport.classpath.resources.WithResource;
 import org.springframework.boot.web.codec.CodecCustomizer;
 import org.springframework.boot.web.reactive.context.ReactiveWebApplicationContext;
 import org.springframework.boot.web.reactive.filter.OrderedHiddenHttpMethodFilter;
+import org.springframework.boot.web.reactive.server.MockReactiveWebServerFactory;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/FilterOrderingIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -28,11 +28,12 @@ import org.springframework.boot.autoconfigure.http.HttpMessageConvertersAutoConf
 import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration;
 import org.springframework.boot.autoconfigure.session.SessionAutoConfiguration;
 import org.springframework.boot.test.util.TestPropertyValues;
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredFilter;
 import org.springframework.boot.web.server.WebServerFactoryCustomizerBeanPostProcessor;
 import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext;
 import org.springframework.boot.web.servlet.filter.OrderedCharacterEncodingFilter;
 import org.springframework.boot.web.servlet.filter.OrderedRequestContextFilter;
+import org.springframework.boot.web.servlet.server.MockServletWebServer.RegisteredFilter;
+import org.springframework.boot.web.servlet.server.MockServletWebServerFactory;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.data.redis.connection.RedisConnection;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/HttpEncodingAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -33,6 +33,7 @@ import org.springframework.boot.web.server.WebServerFactoryCustomizerBeanPostPro
 import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebApplicationContext;
 import org.springframework.boot.web.servlet.filter.OrderedFormContentFilter;
 import org.springframework.boot.web.servlet.filter.OrderedHiddenHttpMethodFilter;
+import org.springframework.boot.web.servlet.server.MockServletWebServerFactory;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/MockServletWebServerFactory.java

@@ -1,79 +0,0 @@
-/*
- * Copyright 2012-2023 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.autoconfigure.web.servlet;
-
-import java.util.Arrays;
-
-import jakarta.servlet.ServletContext;
-
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredFilter;
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredServlet;
-import org.springframework.boot.web.server.WebServer;
-import org.springframework.boot.web.servlet.ServletContextInitializer;
-import org.springframework.boot.web.servlet.server.AbstractServletWebServerFactory;
-import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
-
-import static org.mockito.Mockito.spy;
-
-/**
- * Mock {@link ServletWebServerFactory}.
- *
- * @author Phillip Webb
- * @author Andy Wilkinson
- */
-public class MockServletWebServerFactory extends AbstractServletWebServerFactory {
-
-	private MockServletWebServer webServer;
-
-	@Override
-	public WebServer getWebServer(ServletContextInitializer... initializers) {
-		this.webServer = spy(new MockServletWebServer(mergeInitializers(initializers), getPort()));
-		return this.webServer;
-	}
-
-	public MockServletWebServer getWebServer() {
-		return this.webServer;
-	}
-
-	public ServletContext getServletContext() {
-		return (getWebServer() != null) ? getWebServer().getServletContext() : null;
-	}
-
-	public RegisteredServlet getRegisteredServlet(int index) {
-		return (getWebServer() != null) ? getWebServer().getRegisteredServlet(index) : null;
-	}
-
-	public RegisteredFilter getRegisteredFilter(int index) {
-		return (getWebServer() != null) ? getWebServer().getRegisteredFilters(index) : null;
-	}
-
-	static class MockServletWebServer extends org.springframework.boot.testsupport.web.servlet.MockServletWebServer
-			implements WebServer {
-
-		MockServletWebServer(ServletContextInitializer[] initializers, int port) {
-			super(Arrays.stream(initializers)
-				.map((initializer) -> (Initializer) initializer::onStartup)
-				.toArray(Initializer[]::new), port);
-		}
-
-		@Override
-		public void start() {
-		}
-
-	}
-
-}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/ServletWebServerFactoryAutoConfigurationTests.java

@@ -47,6 +47,7 @@ import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebSe
 import org.springframework.boot.web.servlet.server.AbstractServletWebServerFactory;
 import org.springframework.boot.web.servlet.server.ConfigurableServletWebServerFactory;
 import org.springframework.boot.web.servlet.server.CookieSameSiteSupplier;
+import org.springframework.boot.web.servlet.server.MockServletWebServerFactory;
 import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfigurationTests.java

@@ -64,6 +64,7 @@ import org.springframework.boot.web.servlet.FilterRegistrationBean;
 import org.springframework.boot.web.servlet.ServletRegistrationBean;
 import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext;
 import org.springframework.boot.web.servlet.filter.OrderedFormContentFilter;
+import org.springframework.boot.web.servlet.server.MockServletWebServerFactory;
 import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/main/java/org/springframework/boot/testsupport/classpath/resources/Resources.java

@@ -18,21 +18,26 @@ package org.springframework.boot.testsupport.classpath.resources;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
+import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.nio.file.FileSystem;
+import java.nio.file.FileSystemNotFoundException;
+import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
 import org.springframework.util.Assert;
 import org.springframework.util.FileSystemUtils;
+import org.springframework.util.function.ThrowingConsumer;
 
 /**
  * A collection of resources.
@@ -50,27 +55,43 @@ class Resources {
 	}
 
 	Resources addPackage(Package root, String[] resourceNames) {
+		String packageName = root.getName();
 		Set<String> unmatchedNames = new HashSet<>(Arrays.asList(resourceNames));
+		withPathsForPackage(packageName, (packagePath) -> {
+			for (String resourceName : resourceNames) {
+				Path resource = packagePath.resolve(resourceName);
+				if (Files.exists(resource) && !Files.isDirectory(resource)) {
+					Path target = this.root.resolve(resourceName);
+					Path targetDirectory = target.getParent();
+					if (!Files.isDirectory(targetDirectory)) {
+						Files.createDirectories(targetDirectory);
+					}
+					Files.copy(resource, target);
+					register(resourceName, target, true);
+					unmatchedNames.remove(resourceName);
+				}
+			}
+		});
+		Assert.isTrue(unmatchedNames.isEmpty(),
+				"Package '" + packageName + "' did not contain resources: " + unmatchedNames);
+		return this;
+	}
+
+	private void withPathsForPackage(String packageName, ThrowingConsumer<Path> consumer) {
 		try {
-			Enumeration<URL> sources = getClass().getClassLoader().getResources(root.getName().replace(".", "/"));
-			for (URL source : Collections.list(sources)) {
-				Path sourceRoot = Paths.get(source.toURI());
-				for (String resourceName : resourceNames) {
-					Path resource = sourceRoot.resolve(resourceName);
-					if (Files.isRegularFile(resource)) {
-						Path target = this.root.resolve(resourceName);
-						Path targetDirectory = target.getParent();
-						if (!Files.isDirectory(targetDirectory)) {
-							Files.createDirectories(targetDirectory);
-						}
-						Files.copy(resource, target);
-						register(resourceName, target, true);
-						unmatchedNames.remove(resourceName);
+			List<URL> sources = Collections
+				.list(getClass().getClassLoader().getResources(packageName.replace(".", "/")));
+			for (URL source : sources) {
+				URI sourceUri = source.toURI();
+				try {
+					consumer.accept(Paths.get(sourceUri));
+				}
+				catch (FileSystemNotFoundException ex) {
+					try (FileSystem fileSystem = FileSystems.newFileSystem(sourceUri, Collections.emptyMap())) {
+						consumer.accept(Paths.get(sourceUri));
 					}
 				}
 			}
-			Assert.isTrue(unmatchedNames.isEmpty(),
-					"Package '" + root.getName() + "' did not contain resources: " + unmatchedNames);
 		}
 		catch (IOException ex) {
 			throw new UncheckedIOException(ex);
@@ -78,7 +99,6 @@ class Resources {
 		catch (URISyntaxException ex) {
 			throw new RuntimeException(ex);
 		}
-		return this;
 	}
 
 	Resources addResource(String name, String content, boolean additional) {

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/test/java/org/springframework/boot/testsupport/web/servlet/MockServletWebServerTests.java

@@ -1,56 +0,0 @@
-/*
- * Copyright 2012-2023 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.testsupport.web.servlet;
-
-import org.junit.jupiter.api.Test;
-
-import org.springframework.mock.web.MockSessionCookieConfig;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-/**
- * Tests for {@link MockServletWebServer}.
- *
- * @author Stephane Nicoll
- */
-class MockServletWebServerTests {
-
-	@Test
-	void servletContextIsConfigured() {
-		MockServletWebServer server = TestMockServletWebServer.create();
-		assertThat(server.getServletContext()).isNotNull();
-	}
-
-	@Test
-	void servletContextHasSessionCookieConfigConfigured() {
-		MockServletWebServer server = TestMockServletWebServer.create();
-		assertThat(server.getServletContext().getSessionCookieConfig()).isInstanceOf(MockSessionCookieConfig.class);
-	}
-
-	private static final class TestMockServletWebServer extends MockServletWebServer {
-
-		private TestMockServletWebServer(Initializer[] initializers, int port) {
-			super(initializers, port);
-		}
-
-		static MockServletWebServer create(Initializer... initializers) {
-			return new TestMockServletWebServer(initializers, 8080);
-		}
-
-	}
-
-}

spring-boot-project/spring-boot/build.gradle

@@ -1,6 +1,7 @@
 plugins {
 	id "dev.adamko.dokkatoo-html"
 	id "java-library"
+	id "java-test-fixtures"
 	id "org.jetbrains.kotlin.jvm"
 	id "org.springframework.boot.configuration-properties"
 	id "org.springframework.boot.deployed"
@@ -99,6 +100,10 @@ dependencies {
 	optional("org.yaml:snakeyaml")
 	optional("org.jetbrains.kotlin:kotlin-reflect")
 	optional("org.jetbrains.kotlin:kotlin-stdlib")
+	
+	testFixturesCompileOnly("jakarta.servlet:jakarta.servlet-api")
+	testFixturesCompileOnly("org.mockito:mockito-core")
+	testFixturesCompileOnly("org.springframework:spring-web")
 
 	testImplementation(project(":spring-boot-project:spring-boot-tools:spring-boot-test-support"))
 	testImplementation("org.springframework:spring-core-test")

spring-boot-project/spring-boot/src/testFixtures/java/org/springframework/boot/web/reactive/server/MockReactiveWebServer.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2012-2025 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.
+ * 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.web.reactive.server;
+
+import java.util.Map;
+
+import org.springframework.boot.web.server.WebServer;
+import org.springframework.http.server.reactive.HttpHandler;
+
+/**
+ * A mock reactive {@link WebServer}.
+ *
+ * @author Brian Clozel
+ */
+public class MockReactiveWebServer implements WebServer {
+
+	private final int port;
+
+	private HttpHandler httpHandler;
+
+	private Map<String, HttpHandler> httpHandlerMap;
+
+	MockReactiveWebServer(HttpHandler httpHandler, int port) {
+		this.httpHandler = httpHandler;
+		this.port = port;
+	}
+
+	MockReactiveWebServer(Map<String, HttpHandler> httpHandlerMap, int port) {
+		this.httpHandlerMap = httpHandlerMap;
+		this.port = port;
+	}
+
+	public HttpHandler getHttpHandler() {
+		return this.httpHandler;
+	}
+
+	public Map<String, HttpHandler> getHttpHandlerMap() {
+		return this.httpHandlerMap;
+	}
+
+	@Override
+	public void start() {
+
+	}
+
+	@Override
+	public void stop() {
+
+	}
+
+	@Override
+	public int getPort() {
+		return this.port;
+	}
+
+}

spring-boot-project/spring-boot/src/testFixtures/java/org/springframework/boot/web/reactive/server/MockReactiveWebServerFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -16,8 +16,6 @@
 
 package org.springframework.boot.web.reactive.server;
 
-import java.util.Map;
-
 import org.springframework.boot.web.server.WebServer;
 import org.springframework.http.server.reactive.HttpHandler;
 
@@ -42,47 +40,4 @@ public class MockReactiveWebServerFactory extends AbstractReactiveWebServerFacto
 		return this.webServer;
 	}
 
-	public static class MockReactiveWebServer implements WebServer {
-
-		private final int port;
-
-		private HttpHandler httpHandler;
-
-		private Map<String, HttpHandler> httpHandlerMap;
-
-		MockReactiveWebServer(HttpHandler httpHandler, int port) {
-			this.httpHandler = httpHandler;
-			this.port = port;
-		}
-
-		MockReactiveWebServer(Map<String, HttpHandler> httpHandlerMap, int port) {
-			this.httpHandlerMap = httpHandlerMap;
-			this.port = port;
-		}
-
-		public HttpHandler getHttpHandler() {
-			return this.httpHandler;
-		}
-
-		public Map<String, HttpHandler> getHttpHandlerMap() {
-			return this.httpHandlerMap;
-		}
-
-		@Override
-		public void start() {
-
-		}
-
-		@Override
-		public void stop() {
-
-		}
-
-		@Override
-		public int getPort() {
-			return this.port;
-		}
-
-	}
-
 }

spring-boot-project/spring-boot/src/testFixtures/java/org/springframework/boot/web/servlet/server/MockServletWebServer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.testsupport.web.servlet;
+package org.springframework.boot.web.servlet.server;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -31,6 +31,9 @@ import jakarta.servlet.ServletException;
 import jakarta.servlet.ServletRegistration;
 import jakarta.servlet.SessionCookieConfig;
 
+import org.springframework.boot.web.server.WebServer;
+import org.springframework.boot.web.server.WebServerException;
+import org.springframework.boot.web.servlet.ServletContextInitializer;
 import org.springframework.mock.web.MockSessionCookieConfig;
 
 import static org.mockito.ArgumentMatchers.any;
@@ -40,14 +43,12 @@ import static org.mockito.Mockito.lenient;
 import static org.mockito.Mockito.mock;
 
 /**
- * Base class for Mock {@code ServletWebServer} implementations. Reduces the amount of
- * code that would otherwise be duplicated in {@code spring-boot},
- * {@code spring-boot-autoconfigure} and {@code spring-boot-actuator}.
+ * A mock servlet {@link WebServer}.
  *
  * @author Phillip Webb
  * @author Andy Wilkinson
  */
-public abstract class MockServletWebServer {
+public class MockServletWebServer implements WebServer {
 
 	private ServletContext servletContext;
 
@@ -59,7 +60,13 @@ public abstract class MockServletWebServer {
 
 	private final int port;
 
-	public MockServletWebServer(Initializer[] initializers, int port) {
+	MockServletWebServer(ServletContextInitializer[] initializers, int port) {
+		this(Arrays.stream(initializers)
+			.map((initializer) -> (Initializer) initializer::onStartup)
+			.toArray(Initializer[]::new), port);
+	}
+
+	MockServletWebServer(Initializer[] initializers, int port) {
 		this.initializers = initializers;
 		this.port = port;
 		initialize();
@@ -100,6 +107,11 @@ public abstract class MockServletWebServer {
 		}
 	}
 
+	@Override
+	public void start() throws WebServerException {
+	}
+
+	@Override
 	public void stop() {
 		this.servletContext = null;
 		this.registeredServlets.clear();
@@ -131,6 +143,7 @@ public abstract class MockServletWebServer {
 		return this.registeredFilters;
 	}
 
+	@Override
 	public int getPort() {
 		return this.port;
 	}
@@ -184,7 +197,7 @@ public abstract class MockServletWebServer {
 	}
 
 	/**
-	 * Initializer (usually implement by adapting {@code Initializer}).
+	 * Initializer (usually implement by adapting {@code ServletContextInitializer}).
 	 */
 	@FunctionalInterface
 	protected interface Initializer {

spring-boot-project/spring-boot/src/testFixtures/java/org/springframework/boot/web/servlet/server/MockServletWebServerFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 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.
@@ -16,14 +16,12 @@
 
 package org.springframework.boot.web.servlet.server;
 
-import java.util.Arrays;
-
 import jakarta.servlet.ServletContext;
 
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredFilter;
-import org.springframework.boot.testsupport.web.servlet.MockServletWebServer.RegisteredServlet;
 import org.springframework.boot.web.server.WebServer;
 import org.springframework.boot.web.servlet.ServletContextInitializer;
+import org.springframework.boot.web.servlet.server.MockServletWebServer.RegisteredFilter;
+import org.springframework.boot.web.servlet.server.MockServletWebServer.RegisteredServlet;
 
 import static org.mockito.Mockito.spy;
 
@@ -59,19 +57,4 @@ public class MockServletWebServerFactory extends AbstractServletWebServerFactory
 		return (getWebServer() != null) ? getWebServer().getRegisteredFilters(index) : null;
 	}
 
-	public static class MockServletWebServer
-			extends org.springframework.boot.testsupport.web.servlet.MockServletWebServer implements WebServer {
-
-		MockServletWebServer(ServletContextInitializer[] initializers, int port) {
-			super(Arrays.stream(initializers)
-				.map((initializer) -> (Initializer) initializer::onStartup)
-				.toArray(Initializer[]::new), port);
-		}
-
-		@Override
-		public void start() {
-		}
-
-	}
-
 }

src/checkstyle/checkstyle-suppressions.xml

@@ -22,7 +22,7 @@
 	<suppress files="[\\/]src[\\/]test[\\/]java[\\/]cli[\\/]command[\\/]" checks="ImportControl" />
 	<suppress files="[\\/]src[\\/]main[\\/]java[\\/]sample[\\/]" checks="ImportControl" />
 	<suppress files="[\\/]src[\\/]test[\\/]java[\\/]sample[\\/]" checks="ImportControl" />
-	<suppress files="[\\/]src[\\/]test[\\/]java[\\/]" checks="Javadoc*" />
+	<suppress files="[\\/]src[\\/]test(Fixtures)?[\\/]java[\\/]" checks="Javadoc*" />
 	<suppress files="[\\/]src[\\/]test[\\/]java[\\/]" id="mainCodeIllegalImportCheck" />
 	<suppress files="[\\/]src[\\/]test[\\/]java[\\/]" checks="NonEmptyAtclauseDescription" />
 	<suppress files="[\\/]autoconfigure[\\/].*Properties\.java" checks="JavadocType" />