Fix: Replace HandlerMappingIntrospector with PreFlightRequestHandler bean in MVC config

spring-webmvc/src/main/java/org/springframework/web/servlet/config/MvcNamespaceUtils.java

@@ -35,7 +35,6 @@
 import org.springframework.web.servlet.DispatcherServlet;
 import org.springframework.web.servlet.handler.AbstractHandlerMapping;
 import org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping;
-import org.springframework.web.servlet.handler.HandlerMappingIntrospector;
 import org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver;
 import org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter;
 import org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter;
@@ -72,14 +71,11 @@ public abstract class MvcNamespaceUtils {
 
 	private static final String CORS_CONFIGURATION_BEAN_NAME = "mvcCorsConfigurations";
 
-	private static final String HANDLER_MAPPING_INTROSPECTOR_BEAN_NAME = "mvcHandlerMappingIntrospector";
-
 
 	public static void registerDefaultComponents(ParserContext context, @Nullable Object source) {
 		registerBeanNameUrlHandlerMapping(context, source);
 		registerHttpRequestHandlerAdapter(context, source);
 		registerSimpleControllerHandlerAdapter(context, source);
-		registerHandlerMappingIntrospector(context, source);
 		registerLocaleResolver(context, source);
 		registerViewNameTranslator(context, source);
 		registerFlashMapManager(context, source);
@@ -275,22 +271,6 @@ else if (corsConfigurations != null) {
 		return new RuntimeBeanReference(CORS_CONFIGURATION_BEAN_NAME);
 	}
 
-	/**
-	 * Registers an {@link HandlerMappingIntrospector} under a well-known name
-	 * unless already registered.
-	 */
-	@SuppressWarnings("removal")
-	private static void registerHandlerMappingIntrospector(ParserContext context, @Nullable Object source) {
-		if (!context.getRegistry().containsBeanDefinition(HANDLER_MAPPING_INTROSPECTOR_BEAN_NAME)) {
-			RootBeanDefinition beanDef = new RootBeanDefinition(HandlerMappingIntrospector.class);
-			beanDef.setSource(source);
-			beanDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
-			beanDef.setLazyInit(true);
-			context.getRegistry().registerBeanDefinition(HANDLER_MAPPING_INTROSPECTOR_BEAN_NAME, beanDef);
-			context.registerComponent(new BeanComponentDefinition(beanDef, HANDLER_MAPPING_INTROSPECTOR_BEAN_NAME));
-		}
-	}
-
 	/**
 	 * Registers an {@link AcceptHeaderLocaleResolver} under a well-known name
 	 * unless already registered.

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurationSupport.java

@@ -35,7 +35,6 @@
 import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.Lazy;
 import org.springframework.core.KotlinDetector;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.format.Formatter;
@@ -61,6 +60,7 @@
 import org.springframework.web.bind.support.ConfigurableWebBindingInitializer;
 import org.springframework.web.context.ServletContextAware;
 import org.springframework.web.cors.CorsConfiguration;
+import org.springframework.web.cors.PreFlightRequestHandler;
 import org.springframework.web.method.support.CompositeUriComponentsContributor;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
@@ -76,8 +76,8 @@
 import org.springframework.web.servlet.handler.AbstractHandlerMapping;
 import org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping;
 import org.springframework.web.servlet.handler.ConversionServiceExposingInterceptor;
+import org.springframework.web.servlet.handler.DefaultPreFlightRequestHandler;
 import org.springframework.web.servlet.handler.HandlerExceptionResolverComposite;
-import org.springframework.web.servlet.handler.HandlerMappingIntrospector;
 import org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver;
 import org.springframework.web.servlet.mvc.Controller;
 import org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter;
@@ -1161,11 +1161,9 @@ protected final Map<String, CorsConfiguration> getCorsConfigurations() {
 	protected void addCorsMappings(CorsRegistry registry) {
 	}
 
-	@SuppressWarnings("removal")
 	@Bean
-	@Lazy
-	public HandlerMappingIntrospector mvcHandlerMappingIntrospector() {
-		return new HandlerMappingIntrospector();
+	public PreFlightRequestHandler preFlightRequestHandler() {
+		return new DefaultPreFlightRequestHandler();
 	}
 
 	@Bean

spring-webmvc/src/main/java/org/springframework/web/servlet/handler/AbstractHandlerMapping.java

@@ -762,7 +762,7 @@ private class CorsInterceptor implements HandlerInterceptor, CorsConfigurationSo
 
 		private final @Nullable CorsConfiguration config;
 
-		public CorsInterceptor(@Nullable CorsConfiguration config) {
+		CorsInterceptor(@Nullable CorsConfiguration config) {
 			this.config = config;
 		}
 
@@ -795,7 +795,7 @@ protected boolean invokeCorsProcessor(
 	private final class PreFlightHttpRequestHandler
 			extends CorsInterceptor implements HttpRequestHandler, PreFlightRequestHandler {
 
-		public PreFlightHttpRequestHandler(@Nullable CorsConfiguration config) {
+		PreFlightHttpRequestHandler(@Nullable CorsConfiguration config) {
 			super(config);
 		}
 

spring-webmvc/src/main/java/org/springframework/web/servlet/handler/DefaultPreFlightRequestHandler.java

@@ -0,0 +1,157 @@
+/*
+ * Copyright 2002-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.web.servlet.handler;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.beans.factory.BeanFactoryUtils;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.core.annotation.AnnotationAwareOrderComparator;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.PropertiesLoaderUtils;
+import org.springframework.http.server.RequestPath;
+import org.springframework.http.server.ServletServerHttpRequest;
+import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
+import org.springframework.util.StringUtils;
+import org.springframework.web.cors.CorsUtils;
+import org.springframework.web.cors.PreFlightRequestHandler;
+import org.springframework.web.servlet.DispatcherServlet;
+import org.springframework.web.servlet.HandlerExecutionChain;
+import org.springframework.web.servlet.HandlerMapping;
+import org.springframework.web.servlet.NoHandlerFoundException;
+import org.springframework.web.util.ServletRequestPathUtils;
+
+/**
+ * Default implementation of {@link PreFlightRequestHandler} that discovers all
+ * {@link HandlerMapping} beans in the {@link ApplicationContext} and uses them to
+ * find a handler for a pre-flight CORS request, then delegates to the
+ * {@link PreFlightRequestHandler} returned by that mapping.
+ *
+ * <p>Handler mappings are detected and sorted in the same way as in
+ * {@link DispatcherServlet}, with fallback to the default mappings configured in
+ * {@code DispatcherServlet.properties} if no mappings are found.
+ *
+ * @author Rossen Stoyanchev
+ * @since 7.1
+ * @see PreFlightRequestHandler
+ * @see HandlerMapping
+ * @see DispatcherServlet
+ */
+public class DefaultPreFlightRequestHandler
+		implements PreFlightRequestHandler, ApplicationContextAware, InitializingBean {
+
+	private @Nullable ApplicationContext applicationContext;
+
+	private @Nullable List<HandlerMapping> handlerMappings;
+
+	@Override
+	public void setApplicationContext(ApplicationContext applicationContext) {
+		this.applicationContext = applicationContext;
+	}
+
+	@Override
+	public void afterPropertiesSet() {
+		if (this.handlerMappings == null) {
+			Assert.notNull(this.applicationContext, "No ApplicationContext");
+			this.handlerMappings = initHandlerMappings(this.applicationContext);
+		}
+	}
+
+	private static List<HandlerMapping> initHandlerMappings(ApplicationContext context) {
+		Map<String, HandlerMapping> beans =
+				BeanFactoryUtils.beansOfTypeIncludingAncestors(context, HandlerMapping.class, true, false);
+
+		if (!beans.isEmpty()) {
+			List<HandlerMapping> mappings = new ArrayList<>(beans.values());
+			AnnotationAwareOrderComparator.sort(mappings);
+			return Collections.unmodifiableList(mappings);
+		}
+
+		return Collections.unmodifiableList(initFallback(context));
+	}
+
+	private static List<HandlerMapping> initFallback(ApplicationContext applicationContext) {
+		Properties properties;
+		try {
+			Resource resource = new ClassPathResource("DispatcherServlet.properties", DispatcherServlet.class);
+			properties = PropertiesLoaderUtils.loadProperties(resource);
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException("Could not load DispatcherServlet.properties: " + ex.getMessage());
+		}
+
+		String value = properties.getProperty(HandlerMapping.class.getName());
+		String[] names = StringUtils.commaDelimitedListToStringArray(value);
+		List<HandlerMapping> result = new ArrayList<>(names.length);
+		for (String name : names) {
+			try {
+				Class<?> clazz = ClassUtils.forName(name, DispatcherServlet.class.getClassLoader());
+				Object mapping = applicationContext.getAutowireCapableBeanFactory().createBean(clazz);
+				result.add((HandlerMapping) mapping);
+			}
+			catch (ClassNotFoundException ex) {
+				throw new IllegalStateException("Could not find default HandlerMapping [" + name + "]");
+			}
+		}
+		return result;
+	}
+
+	/**
+	 * Find the matching {@link HandlerMapping} for the request, and invoke the
+	 * handler it returns as a {@link PreFlightRequestHandler}.
+	 * @throws NoHandlerFoundException if no handler matches the request
+	 * @since 7.1
+	 */
+	@Override
+	public void handlePreFlight(HttpServletRequest request, HttpServletResponse response) throws Exception {
+		Assert.state(this.handlerMappings != null, "Not yet initialized via afterPropertiesSet.");
+		Assert.state(CorsUtils.isPreFlightRequest(request), "Not a pre-flight request.");
+		RequestPath previousPath = (RequestPath) request.getAttribute(ServletRequestPathUtils.PATH_ATTRIBUTE);
+		try {
+			ServletRequestPathUtils.parseAndCache(request);
+			for (HandlerMapping mapping : this.handlerMappings) {
+				HandlerExecutionChain chain = mapping.getHandler(request);
+				if (chain != null) {
+					Object handler = chain.getHandler();
+					if (handler instanceof PreFlightRequestHandler preFlightHandler) {
+						preFlightHandler.handlePreFlight(request, response);
+						return;
+					}
+					throw new IllegalStateException("Expected PreFlightRequestHandler: " + handler.getClass());
+				}
+			}
+			throw new NoHandlerFoundException(
+					request.getMethod(), request.getRequestURI(), new ServletServerHttpRequest(request).getHeaders());
+		}
+		finally {
+			ServletRequestPathUtils.setParsedRequestPath(previousPath, request);
+		}
+	}
+}