org.springframework/spring-webmvc/5.3.3 : org/springframework/web/servlet/mvc/method/annotation/RequestMappingHandlerAdapter.java

RequestMappingHandlerAdapter
https://github.com/spring-projects/spring-framework: Spring Web MVC (Spring IO)
Apache License, Version 2.0
Juergen Hoeller
/*
 * Copyright 2002-2020 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.mvc.method.annotation;

import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.KotlinDetector;
import org.springframework.core.MethodIntrospector;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.core.ReactiveAdapterRegistry;
import org.springframework.core.SpringProperties;
import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.core.log.LogFormatUtils;
import org.springframework.core.task.AsyncTaskExecutor;
import org.springframework.core.task.SimpleAsyncTaskExecutor;
import org.springframework.http.converter.ByteArrayHttpMessageConverter;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.http.converter.support.AllEncompassingFormHttpMessageConverter;
import org.springframework.http.converter.xml.SourceHttpMessageConverter;
import org.springframework.lang.Nullable;
import org.springframework.ui.ModelMap;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ReflectionUtils.MethodFilter;
import org.springframework.web.accept.ContentNegotiationManager;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.support.DefaultDataBinderFactory;
import org.springframework.web.bind.support.DefaultSessionAttributeStore;
import org.springframework.web.bind.support.SessionAttributeStore;
import org.springframework.web.bind.support.WebBindingInitializer;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.ServletWebRequest;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.context.request.async.AsyncWebRequest;
import org.springframework.web.context.request.async.CallableProcessingInterceptor;
import org.springframework.web.context.request.async.DeferredResultProcessingInterceptor;
import org.springframework.web.context.request.async.WebAsyncManager;
import org.springframework.web.context.request.async.WebAsyncTask;
import org.springframework.web.context.request.async.WebAsyncUtils;
import org.springframework.web.method.ControllerAdviceBean;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.method.annotation.ErrorsMethodArgumentResolver;
import org.springframework.web.method.annotation.ExpressionValueMethodArgumentResolver;
import org.springframework.web.method.annotation.InitBinderDataBinderFactory;
import org.springframework.web.method.annotation.MapMethodProcessor;
import org.springframework.web.method.annotation.ModelFactory;
import org.springframework.web.method.annotation.ModelMethodProcessor;
import org.springframework.web.method.annotation.RequestHeaderMapMethodArgumentResolver;
import org.springframework.web.method.annotation.RequestHeaderMethodArgumentResolver;
import org.springframework.web.method.annotation.RequestParamMapMethodArgumentResolver;
import org.springframework.web.method.annotation.RequestParamMethodArgumentResolver;
import org.springframework.web.method.annotation.SessionAttributesHandler;
import org.springframework.web.method.annotation.SessionStatusMethodArgumentResolver;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.HandlerMethodArgumentResolverComposite;
import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
import org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite;
import org.springframework.web.method.support.InvocableHandlerMethod;
import org.springframework.web.method.support.ModelAndViewContainer;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.mvc.annotation.ModelAndViewResolver;
import org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
import org.springframework.web.servlet.support.RequestContextUtils;
import org.springframework.web.util.WebUtils;

Extension of AbstractHandlerMethodAdapter that supports @RequestMapping annotated HandlerMethods. Support for custom argument and return value types can be added via setCustomArgumentResolvers and setCustomReturnValueHandlers, or alternatively, to re-configure all argument and return value types, use setArgumentResolvers and setReturnValueHandlers. 
Author: Rossen Stoyanchev, Juergen Hoeller, Sebastien Deleuze
See Also: HandlerMethodArgumentResolver
HandlerMethodReturnValueHandler
Since: 3.1/**
 * Extension of {@link AbstractHandlerMethodAdapter} that supports
 * {@link RequestMapping @RequestMapping} annotated {@link HandlerMethod HandlerMethods}.
 *
 * <p>Support for custom argument and return value types can be added via
 * {@link #setCustomArgumentResolvers} and {@link #setCustomReturnValueHandlers},
 * or alternatively, to re-configure all argument and return value types,
 * use {@link #setArgumentResolvers} and {@link #setReturnValueHandlers}.
 *
 * @author Rossen Stoyanchev
 * @author Juergen Hoeller
 * @author Sebastien Deleuze
 * @since 3.1
 * @see HandlerMethodArgumentResolver
 * @see HandlerMethodReturnValueHandler
 */
public class RequestMappingHandlerAdapter extends AbstractHandlerMethodAdapter
		implements BeanFactoryAware, InitializingBean {

	Boolean flag controlled by a spring.xml.ignore system property that instructs Spring to ignore XML, i.e. to not initialize the XML-related infrastructure. The default is "false".
/**
	 * Boolean flag controlled by a {@code spring.xml.ignore} system property that instructs Spring to
	 * ignore XML, i.e. to not initialize the XML-related infrastructure.
	 * <p>The default is "false".
	 */
	private static final boolean shouldIgnoreXml = SpringProperties.getFlag("spring.xml.ignore");

	MethodFilter that matches @InitBinder methods. /**
	 * MethodFilter that matches {@link InitBinder @InitBinder} methods.
	 */
	public static final MethodFilter INIT_BINDER_METHODS = method ->
			AnnotatedElementUtils.hasAnnotation(method, InitBinder.class);

	MethodFilter that matches @ModelAttribute methods. /**
	 * MethodFilter that matches {@link ModelAttribute @ModelAttribute} methods.
	 */
	public static final MethodFilter MODEL_ATTRIBUTE_METHODS = method ->
			(!AnnotatedElementUtils.hasAnnotation(method, RequestMapping.class) &&
					AnnotatedElementUtils.hasAnnotation(method, ModelAttribute.class));


	@Nullable
	private List<HandlerMethodArgumentResolver> customArgumentResolvers;

	@Nullable
	private HandlerMethodArgumentResolverComposite argumentResolvers;

	@Nullable
	private HandlerMethodArgumentResolverComposite initBinderArgumentResolvers;

	@Nullable
	private List<HandlerMethodReturnValueHandler> customReturnValueHandlers;

	@Nullable
	private HandlerMethodReturnValueHandlerComposite returnValueHandlers;

	@Nullable
	private List<ModelAndViewResolver> modelAndViewResolvers;

	private ContentNegotiationManager contentNegotiationManager = new ContentNegotiationManager();

	private List<HttpMessageConverter<?>> messageConverters;

	private final List<Object> requestResponseBodyAdvice = new ArrayList<>();

	@Nullable
	private WebBindingInitializer webBindingInitializer;

	private AsyncTaskExecutor taskExecutor = new SimpleAsyncTaskExecutor("MvcAsync");

	@Nullable
	private Long asyncRequestTimeout;

	private CallableProcessingInterceptor[] callableInterceptors = new CallableProcessingInterceptor[0];

	private DeferredResultProcessingInterceptor[] deferredResultInterceptors = new DeferredResultProcessingInterceptor[0];

	private ReactiveAdapterRegistry reactiveAdapterRegistry = ReactiveAdapterRegistry.getSharedInstance();

	private boolean ignoreDefaultModelOnRedirect = false;

	private int cacheSecondsForSessionAttributeHandlers = 0;

	private boolean synchronizeOnSession = false;

	private SessionAttributeStore sessionAttributeStore = new DefaultSessionAttributeStore();

	private ParameterNameDiscoverer parameterNameDiscoverer = new DefaultParameterNameDiscoverer();

	@Nullable
	private ConfigurableBeanFactory beanFactory;

	private final Map<Class<?>, SessionAttributesHandler> sessionAttributesHandlerCache = new ConcurrentHashMap<>(64);

	private final Map<Class<?>, Set<Method>> initBinderCache = new ConcurrentHashMap<>(64);

	private final Map<ControllerAdviceBean, Set<Method>> initBinderAdviceCache = new LinkedHashMap<>();

	private final Map<Class<?>, Set<Method>> modelAttributeCache = new ConcurrentHashMap<>(64);

	private final Map<ControllerAdviceBean, Set<Method>> modelAttributeAdviceCache = new LinkedHashMap<>();


	public RequestMappingHandlerAdapter() {
		this.messageConverters = new ArrayList<>(4);
		this.messageConverters.add(new ByteArrayHttpMessageConverter());
		this.messageConverters.add(new StringHttpMessageConverter());
		if (!shouldIgnoreXml) {
			try {
				this.messageConverters.add(new SourceHttpMessageConverter<>());
			}
			catch (Error err) {
				// Ignore when no TransformerFactory implementation is available
			}
		}
		this.messageConverters.add(new AllEncompassingFormHttpMessageConverter());
	}


	Provide resolvers for custom argument types. Custom resolvers are ordered after built-in ones. To override the built-in support for argument resolution use setArgumentResolvers instead. /**
	 * Provide resolvers for custom argument types. Custom resolvers are ordered
	 * after built-in ones. To override the built-in support for argument
	 * resolution use {@link #setArgumentResolvers} instead.
	 */
	public void setCustomArgumentResolvers(@Nullable List<HandlerMethodArgumentResolver> argumentResolvers) {
		this.customArgumentResolvers = argumentResolvers;
	}

	Return the custom argument resolvers, or null. /**
	 * Return the custom argument resolvers, or {@code null}.
	 */
	@Nullable
	public List<HandlerMethodArgumentResolver> getCustomArgumentResolvers() {
		return this.customArgumentResolvers;
	}

	Configure the complete list of supported argument types thus overriding
the resolvers that would otherwise be configured by default.
/**
	 * Configure the complete list of supported argument types thus overriding
	 * the resolvers that would otherwise be configured by default.
	 */
	public void setArgumentResolvers(@Nullable List<HandlerMethodArgumentResolver> argumentResolvers) {
		if (argumentResolvers == null) {
			this.argumentResolvers = null;
		}
		else {
			this.argumentResolvers = new HandlerMethodArgumentResolverComposite();
			this.argumentResolvers.addResolvers(argumentResolvers);
		}
	}

	Return the configured argument resolvers, or possibly null if not initialized yet via afterPropertiesSet(). /**
	 * Return the configured argument resolvers, or possibly {@code null} if
	 * not initialized yet via {@link #afterPropertiesSet()}.
	 */
	@Nullable
	public List<HandlerMethodArgumentResolver> getArgumentResolvers() {
		return (this.argumentResolvers != null ? this.argumentResolvers.getResolvers() : null);
	}

	Configure the supported argument types in @InitBinder methods. /**
	 * Configure the supported argument types in {@code @InitBinder} methods.
	 */
	public void setInitBinderArgumentResolvers(@Nullable List<HandlerMethodArgumentResolver> argumentResolvers) {
		if (argumentResolvers == null) {
			this.initBinderArgumentResolvers = null;
		}
		else {
			this.initBinderArgumentResolvers = new HandlerMethodArgumentResolverComposite();
			this.initBinderArgumentResolvers.addResolvers(argumentResolvers);
		}
	}

	Return the argument resolvers for @InitBinder methods, or possibly null if not initialized yet via afterPropertiesSet(). /**
	 * Return the argument resolvers for {@code @InitBinder} methods, or possibly
	 * {@code null} if not initialized yet via {@link #afterPropertiesSet()}.
	 */
	@Nullable
	public List<HandlerMethodArgumentResolver> getInitBinderArgumentResolvers() {
		return (this.initBinderArgumentResolvers != null ? this.initBinderArgumentResolvers.getResolvers() : null);
	}

	Provide handlers for custom return value types. Custom handlers are ordered after built-in ones. To override the built-in support for return value handling use setReturnValueHandlers. /**
	 * Provide handlers for custom return value types. Custom handlers are
	 * ordered after built-in ones. To override the built-in support for
	 * return value handling use {@link #setReturnValueHandlers}.
	 */
	public void setCustomReturnValueHandlers(@Nullable List<HandlerMethodReturnValueHandler> returnValueHandlers) {
		this.customReturnValueHandlers = returnValueHandlers;
	}

	Return the custom return value handlers, or null. /**
	 * Return the custom return value handlers, or {@code null}.
	 */
	@Nullable
	public List<HandlerMethodReturnValueHandler> getCustomReturnValueHandlers() {
		return this.customReturnValueHandlers;
	}

	Configure the complete list of supported return value types thus
overriding handlers that would otherwise be configured by default.
/**
	 * Configure the complete list of supported return value types thus
	 * overriding handlers that would otherwise be configured by default.
	 */
	public void setReturnValueHandlers(@Nullable List<HandlerMethodReturnValueHandler> returnValueHandlers) {
		if (returnValueHandlers == null) {
			this.returnValueHandlers = null;
		}
		else {
			this.returnValueHandlers = new HandlerMethodReturnValueHandlerComposite();
			this.returnValueHandlers.addHandlers(returnValueHandlers);
		}
	}

	Return the configured handlers, or possibly null if not initialized yet via afterPropertiesSet(). /**
	 * Return the configured handlers, or possibly {@code null} if not
	 * initialized yet via {@link #afterPropertiesSet()}.
	 */
	@Nullable
	public List<HandlerMethodReturnValueHandler> getReturnValueHandlers() {
		return (this.returnValueHandlers != null ? this.returnValueHandlers.getHandlers() : null);
	}

	Provide custom ModelAndViewResolvers. Note: This method is available for backwards compatibility only. However, it is recommended to re-write a ModelAndViewResolver as HandlerMethodReturnValueHandler. An adapter between the two interfaces is not possible since the HandlerMethodReturnValueHandler.supportsReturnType method cannot be implemented. Hence ModelAndViewResolvers are limited to always being invoked at the end after all other return value handlers have been given a chance. 
A HandlerMethodReturnValueHandler provides better access to the return type and controller method information and can be ordered freely relative to other return value handlers. /**
	 * Provide custom {@link ModelAndViewResolver ModelAndViewResolvers}.
	 * <p><strong>Note:</strong> This method is available for backwards
	 * compatibility only. However, it is recommended to re-write a
	 * {@code ModelAndViewResolver} as {@link HandlerMethodReturnValueHandler}.
	 * An adapter between the two interfaces is not possible since the
	 * {@link HandlerMethodReturnValueHandler#supportsReturnType} method
	 * cannot be implemented. Hence {@code ModelAndViewResolver}s are limited
	 * to always being invoked at the end after all other return value
	 * handlers have been given a chance.
	 * <p>A {@code HandlerMethodReturnValueHandler} provides better access to
	 * the return type and controller method information and can be ordered
	 * freely relative to other return value handlers.
	 */
	public void setModelAndViewResolvers(@Nullable List<ModelAndViewResolver> modelAndViewResolvers) {
		this.modelAndViewResolvers = modelAndViewResolvers;
	}

	Return the configured ModelAndViewResolvers, or null. /**
	 * Return the configured {@link ModelAndViewResolver ModelAndViewResolvers}, or {@code null}.
	 */
	@Nullable
	public List<ModelAndViewResolver> getModelAndViewResolvers() {
		return this.modelAndViewResolvers;
	}

	Set the ContentNegotiationManager to use to determine requested media types. If not set, the default constructor is used. /**
	 * Set the {@link ContentNegotiationManager} to use to determine requested media types.
	 * If not set, the default constructor is used.
	 */
	public void setContentNegotiationManager(ContentNegotiationManager contentNegotiationManager) {
		this.contentNegotiationManager = contentNegotiationManager;
	}

	Provide the converters to use in argument resolvers and return value
handlers that support reading and/or writing to the body of the
request and response.
/**
	 * Provide the converters to use in argument resolvers and return value
	 * handlers that support reading and/or writing to the body of the
	 * request and response.
	 */
	public void setMessageConverters(List<HttpMessageConverter<?>> messageConverters) {
		this.messageConverters = messageConverters;
	}

	Return the configured message body converters.
/**
	 * Return the configured message body converters.
	 */
	public List<HttpMessageConverter<?>> getMessageConverters() {
		return this.messageConverters;
	}

	Add one or more RequestBodyAdvice instances to intercept the request before it is read and converted for @RequestBody and HttpEntity method arguments. /**
	 * Add one or more {@code RequestBodyAdvice} instances to intercept the
	 * request before it is read and converted for {@code @RequestBody} and
	 * {@code HttpEntity} method arguments.
	 */
	public void setRequestBodyAdvice(@Nullable List<RequestBodyAdvice> requestBodyAdvice) {
		if (requestBodyAdvice != null) {
			this.requestResponseBodyAdvice.addAll(requestBodyAdvice);
		}
	}

	Add one or more ResponseBodyAdvice instances to intercept the response before @ResponseBody or ResponseEntity return values are written to the response body. /**
	 * Add one or more {@code ResponseBodyAdvice} instances to intercept the
	 * response before {@code @ResponseBody} or {@code ResponseEntity} return
	 * values are written to the response body.
	 */
	public void setResponseBodyAdvice(@Nullable List<ResponseBodyAdvice<?>> responseBodyAdvice) {
		if (responseBodyAdvice != null) {
			this.requestResponseBodyAdvice.addAll(responseBodyAdvice);
		}
	}

	Provide a WebBindingInitializer with "global" initialization to apply
to every DataBinder instance.
/**
	 * Provide a WebBindingInitializer with "global" initialization to apply
	 * to every DataBinder instance.
	 */
	public void setWebBindingInitializer(@Nullable WebBindingInitializer webBindingInitializer) {
		this.webBindingInitializer = webBindingInitializer;
	}

	Return the configured WebBindingInitializer, or null if none. /**
	 * Return the configured WebBindingInitializer, or {@code null} if none.
	 */
	@Nullable
	public WebBindingInitializer getWebBindingInitializer() {
		return this.webBindingInitializer;
	}

	Set the default AsyncTaskExecutor to use when a controller method return a Callable. Controller methods can override this default on a per-request basis by returning an WebAsyncTask. By default a SimpleAsyncTaskExecutor instance is used. It's recommended to change that default in production as the simple executor does not re-use threads. /**
	 * Set the default {@link AsyncTaskExecutor} to use when a controller method
	 * return a {@link Callable}. Controller methods can override this default on
	 * a per-request basis by returning an {@link WebAsyncTask}.
	 * <p>By default a {@link SimpleAsyncTaskExecutor} instance is used.
	 * It's recommended to change that default in production as the simple executor
	 * does not re-use threads.
	 */
	public void setTaskExecutor(AsyncTaskExecutor taskExecutor) {
		this.taskExecutor = taskExecutor;
	}

	Specify the amount of time, in milliseconds, before concurrent handling
should time out. In Servlet 3, the timeout begins after the main request
processing thread has exited and ends when the request is dispatched again
for further processing of the concurrently produced result.
If this value is not set, the default timeout of the underlying
implementation is used.
Params: timeout – the timeout value in milliseconds/**
	 * Specify the amount of time, in milliseconds, before concurrent handling
	 * should time out. In Servlet 3, the timeout begins after the main request
	 * processing thread has exited and ends when the request is dispatched again
	 * for further processing of the concurrently produced result.
	 * <p>If this value is not set, the default timeout of the underlying
	 * implementation is used.
	 * @param timeout the timeout value in milliseconds
	 */
	public void setAsyncRequestTimeout(long timeout) {
		this.asyncRequestTimeout = timeout;
	}

	Configure CallableProcessingInterceptor's to register on async requests. 
Params: interceptors – the interceptors to register/**
	 * Configure {@code CallableProcessingInterceptor}'s to register on async requests.
	 * @param interceptors the interceptors to register
	 */
	public void setCallableInterceptors(List<CallableProcessingInterceptor> interceptors) {
		this.callableInterceptors = interceptors.toArray(new CallableProcessingInterceptor[0]);
	}

	Configure DeferredResultProcessingInterceptor's to register on async requests. 
Params: interceptors – the interceptors to register/**
	 * Configure {@code DeferredResultProcessingInterceptor}'s to register on async requests.
	 * @param interceptors the interceptors to register
	 */
	public void setDeferredResultInterceptors(List<DeferredResultProcessingInterceptor> interceptors) {
		this.deferredResultInterceptors = interceptors.toArray(new DeferredResultProcessingInterceptor[0]);
	}

	Configure the registry for reactive library types to be supported as
return values from controller methods.
Since: 5.0.5/**
	 * Configure the registry for reactive library types to be supported as
	 * return values from controller methods.
	 * @since 5.0.5
	 */
	public void setReactiveAdapterRegistry(ReactiveAdapterRegistry reactiveAdapterRegistry) {
		this.reactiveAdapterRegistry = reactiveAdapterRegistry;
	}

	Return the configured reactive type registry of adapters.
Since: 5.0/**
	 * Return the configured reactive type registry of adapters.
	 * @since 5.0
	 */
	public ReactiveAdapterRegistry getReactiveAdapterRegistry() {
		return this.reactiveAdapterRegistry;
	}

	By default the content of the "default" model is used both during rendering and redirect scenarios. Alternatively a controller method can declare a RedirectAttributes argument and use it to provide attributes for a redirect. Setting this flag to true guarantees the "default" model is never used in a redirect scenario even if a RedirectAttributes argument is not declared. Setting it to false means the "default" model may be used in a redirect if the controller method doesn't declare a RedirectAttributes argument. 
The default setting is false but new applications should consider setting it to true. 
See Also: RedirectAttributes/**
	 * By default the content of the "default" model is used both during
	 * rendering and redirect scenarios. Alternatively a controller method
	 * can declare a {@link RedirectAttributes} argument and use it to provide
	 * attributes for a redirect.
	 * <p>Setting this flag to {@code true} guarantees the "default" model is
	 * never used in a redirect scenario even if a RedirectAttributes argument
	 * is not declared. Setting it to {@code false} means the "default" model
	 * may be used in a redirect if the controller method doesn't declare a
	 * RedirectAttributes argument.
	 * <p>The default setting is {@code false} but new applications should
	 * consider setting it to {@code true}.
	 * @see RedirectAttributes
	 */
	public void setIgnoreDefaultModelOnRedirect(boolean ignoreDefaultModelOnRedirect) {
		this.ignoreDefaultModelOnRedirect = ignoreDefaultModelOnRedirect;
	}

	Specify the strategy to store session attributes with. The default is DefaultSessionAttributeStore, storing session attributes in the HttpSession with the same attribute name as in the model. /**
	 * Specify the strategy to store session attributes with. The default is
	 * {@link org.springframework.web.bind.support.DefaultSessionAttributeStore},
	 * storing session attributes in the HttpSession with the same attribute
	 * name as in the model.
	 */
	public void setSessionAttributeStore(SessionAttributeStore sessionAttributeStore) {
		this.sessionAttributeStore = sessionAttributeStore;
	}

	Cache content produced by @SessionAttributes annotated handlers for the given number of seconds. Possible values are:

-1: no generation of cache-related headers
0 (default value): "Cache-Control: no-store" will prevent caching
1 or higher: "Cache-Control: max-age=seconds" will ask to cache content;
not advised when dealing with session attributes

In contrast to the "cacheSeconds" property which will apply to all general handlers (but not to @SessionAttributes annotated handlers), this setting will apply to @SessionAttributes handlers only. 
See Also: WebContentGenerator.setCacheSeconds
SessionAttributes/**
	 * Cache content produced by {@code @SessionAttributes} annotated handlers
	 * for the given number of seconds.
	 * <p>Possible values are:
	 * <ul>
	 * <li>-1: no generation of cache-related headers</li>
	 * <li>0 (default value): "Cache-Control: no-store" will prevent caching</li>
	 * <li>1 or higher: "Cache-Control: max-age=seconds" will ask to cache content;
	 * not advised when dealing with session attributes</li>
	 * </ul>
	 * <p>In contrast to the "cacheSeconds" property which will apply to all general
	 * handlers (but not to {@code @SessionAttributes} annotated handlers),
	 * this setting will apply to {@code @SessionAttributes} handlers only.
	 * @see #setCacheSeconds
	 * @see org.springframework.web.bind.annotation.SessionAttributes
	 */
	public void setCacheSecondsForSessionAttributeHandlers(int cacheSecondsForSessionAttributeHandlers) {
		this.cacheSecondsForSessionAttributeHandlers = cacheSecondsForSessionAttributeHandlers;
	}

	Set if controller execution should be synchronized on the session,
to serialize parallel invocations from the same client.
More specifically, the execution of the handleRequestInternal method will get synchronized if this flag is "true". The best available session mutex will be used for the synchronization; ideally, this will be a mutex exposed by HttpSessionMutexListener. 
The session mutex is guaranteed to be the same object during the entire lifetime of the session, available under the key defined by the SESSION_MUTEX_ATTRIBUTE constant. It serves as a safe reference to synchronize on for locking on the current session. 
In many cases, the HttpSession reference itself is a safe mutex
as well, since it will always be the same object reference for the
same active logical session. However, this is not guaranteed across
different servlet containers; the only 100% safe way is a session mutex.
See Also: HttpSessionMutexListener
WebUtils.getSessionMutex(HttpSession)/**
	 * Set if controller execution should be synchronized on the session,
	 * to serialize parallel invocations from the same client.
	 * <p>More specifically, the execution of the {@code handleRequestInternal}
	 * method will get synchronized if this flag is "true". The best available
	 * session mutex will be used for the synchronization; ideally, this will
	 * be a mutex exposed by HttpSessionMutexListener.
	 * <p>The session mutex is guaranteed to be the same object during
	 * the entire lifetime of the session, available under the key defined
	 * by the {@code SESSION_MUTEX_ATTRIBUTE} constant. It serves as a
	 * safe reference to synchronize on for locking on the current session.
	 * <p>In many cases, the HttpSession reference itself is a safe mutex
	 * as well, since it will always be the same object reference for the
	 * same active logical session. However, this is not guaranteed across
	 * different servlet containers; the only 100% safe way is a session mutex.
	 * @see org.springframework.web.util.HttpSessionMutexListener
	 * @see org.springframework.web.util.WebUtils#getSessionMutex(javax.servlet.http.HttpSession)
	 */
	public void setSynchronizeOnSession(boolean synchronizeOnSession) {
		this.synchronizeOnSession = synchronizeOnSession;
	}

	Set the ParameterNameDiscoverer to use for resolving method parameter names if needed
(e.g. for default attribute names).
Default is a DefaultParameterNameDiscoverer. /**
	 * Set the ParameterNameDiscoverer to use for resolving method parameter names if needed
	 * (e.g. for default attribute names).
	 * <p>Default is a {@link org.springframework.core.DefaultParameterNameDiscoverer}.
	 */
	public void setParameterNameDiscoverer(ParameterNameDiscoverer parameterNameDiscoverer) {
		this.parameterNameDiscoverer = parameterNameDiscoverer;
	}

	A ConfigurableBeanFactory is expected for resolving expressions in method argument default values. /**
	 * A {@link ConfigurableBeanFactory} is expected for resolving expressions
	 * in method argument default values.
	 */
	@Override
	public void setBeanFactory(BeanFactory beanFactory) {
		if (beanFactory instanceof ConfigurableBeanFactory) {
			this.beanFactory = (ConfigurableBeanFactory) beanFactory;
		}
	}

	Return the owning factory of this bean instance, or null if none. /**
	 * Return the owning factory of this bean instance, or {@code null} if none.
	 */
	@Nullable
	protected ConfigurableBeanFactory getBeanFactory() {
		return this.beanFactory;
	}


	@Override
	public void afterPropertiesSet() {
		// Do this first, it may add ResponseBody advice beans
		initControllerAdviceCache();

		if (this.argumentResolvers == null) {
			List<HandlerMethodArgumentResolver> resolvers = getDefaultArgumentResolvers();
			this.argumentResolvers = new HandlerMethodArgumentResolverComposite().addResolvers(resolvers);
		}
		if (this.initBinderArgumentResolvers == null) {
			List<HandlerMethodArgumentResolver> resolvers = getDefaultInitBinderArgumentResolvers();
			this.initBinderArgumentResolvers = new HandlerMethodArgumentResolverComposite().addResolvers(resolvers);
		}
		if (this.returnValueHandlers == null) {
			List<HandlerMethodReturnValueHandler> handlers = getDefaultReturnValueHandlers();
			this.returnValueHandlers = new HandlerMethodReturnValueHandlerComposite().addHandlers(handlers);
		}
	}

	private void initControllerAdviceCache() {
		if (getApplicationContext() == null) {
			return;
		}

		List<ControllerAdviceBean> adviceBeans = ControllerAdviceBean.findAnnotatedBeans(getApplicationContext());

		List<Object> requestResponseBodyAdviceBeans = new ArrayList<>();

		for (ControllerAdviceBean adviceBean : adviceBeans) {
			Class<?> beanType = adviceBean.getBeanType();
			if (beanType == null) {
				throw new IllegalStateException("Unresolvable type for ControllerAdviceBean: " + adviceBean);
			}
			Set<Method> attrMethods = MethodIntrospector.selectMethods(beanType, MODEL_ATTRIBUTE_METHODS);
			if (!attrMethods.isEmpty()) {
				this.modelAttributeAdviceCache.put(adviceBean, attrMethods);
			}
			Set<Method> binderMethods = MethodIntrospector.selectMethods(beanType, INIT_BINDER_METHODS);
			if (!binderMethods.isEmpty()) {
				this.initBinderAdviceCache.put(adviceBean, binderMethods);
			}
			if (RequestBodyAdvice.class.isAssignableFrom(beanType) || ResponseBodyAdvice.class.isAssignableFrom(beanType)) {
				requestResponseBodyAdviceBeans.add(adviceBean);
			}
		}

		if (!requestResponseBodyAdviceBeans.isEmpty()) {
			this.requestResponseBodyAdvice.addAll(0, requestResponseBodyAdviceBeans);
		}

		if (logger.isDebugEnabled()) {
			int modelSize = this.modelAttributeAdviceCache.size();
			int binderSize = this.initBinderAdviceCache.size();
			int reqCount = getBodyAdviceCount(RequestBodyAdvice.class);
			int resCount = getBodyAdviceCount(ResponseBodyAdvice.class);
			if (modelSize == 0 && binderSize == 0 && reqCount == 0 && resCount == 0) {
				logger.debug("ControllerAdvice beans: none");
			}
			else {
				logger.debug("ControllerAdvice beans: " + modelSize + " @ModelAttribute, " + binderSize +
						" @InitBinder, " + reqCount + " RequestBodyAdvice, " + resCount + " ResponseBodyAdvice");
			}
		}
	}

	// Count all advice, including explicit registrations..

	private int getBodyAdviceCount(Class<?> adviceType) {
		List<Object> advice = this.requestResponseBodyAdvice;
		return RequestBodyAdvice.class.isAssignableFrom(adviceType) ?
				RequestResponseBodyAdviceChain.getAdviceByType(advice, RequestBodyAdvice.class).size() :
				RequestResponseBodyAdviceChain.getAdviceByType(advice, ResponseBodyAdvice.class).size();
	}

	Return the list of argument resolvers to use including built-in resolvers and custom resolvers provided via setCustomArgumentResolvers. /**
	 * Return the list of argument resolvers to use including built-in resolvers
	 * and custom resolvers provided via {@link #setCustomArgumentResolvers}.
	 */
	private List<HandlerMethodArgumentResolver> getDefaultArgumentResolvers() {
		List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>(30);

		// Annotation-based argument resolution
		resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), false));
		resolvers.add(new RequestParamMapMethodArgumentResolver());
		resolvers.add(new PathVariableMethodArgumentResolver());
		resolvers.add(new PathVariableMapMethodArgumentResolver());
		resolvers.add(new MatrixVariableMethodArgumentResolver());
		resolvers.add(new MatrixVariableMapMethodArgumentResolver());
		resolvers.add(new ServletModelAttributeMethodProcessor(false));
		resolvers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(), this.requestResponseBodyAdvice));
		resolvers.add(new RequestPartMethodArgumentResolver(getMessageConverters(), this.requestResponseBodyAdvice));
		resolvers.add(new RequestHeaderMethodArgumentResolver(getBeanFactory()));
		resolvers.add(new RequestHeaderMapMethodArgumentResolver());
		resolvers.add(new ServletCookieValueMethodArgumentResolver(getBeanFactory()));
		resolvers.add(new ExpressionValueMethodArgumentResolver(getBeanFactory()));
		resolvers.add(new SessionAttributeMethodArgumentResolver());
		resolvers.add(new RequestAttributeMethodArgumentResolver());

		// Type-based argument resolution
		resolvers.add(new ServletRequestMethodArgumentResolver());
		resolvers.add(new ServletResponseMethodArgumentResolver());
		resolvers.add(new HttpEntityMethodProcessor(getMessageConverters(), this.requestResponseBodyAdvice));
		resolvers.add(new RedirectAttributesMethodArgumentResolver());
		resolvers.add(new ModelMethodProcessor());
		resolvers.add(new MapMethodProcessor());
		resolvers.add(new ErrorsMethodArgumentResolver());
		resolvers.add(new SessionStatusMethodArgumentResolver());
		resolvers.add(new UriComponentsBuilderMethodArgumentResolver());
		if (KotlinDetector.isKotlinPresent()) {
			resolvers.add(new ContinuationHandlerMethodArgumentResolver());
		}

		// Custom arguments
		if (getCustomArgumentResolvers() != null) {
			resolvers.addAll(getCustomArgumentResolvers());
		}

		// Catch-all
		resolvers.add(new PrincipalMethodArgumentResolver());
		resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), true));
		resolvers.add(new ServletModelAttributeMethodProcessor(true));

		return resolvers;
	}

	Return the list of argument resolvers to use for @InitBinder methods including built-in and custom resolvers. /**
	 * Return the list of argument resolvers to use for {@code @InitBinder}
	 * methods including built-in and custom resolvers.
	 */
	private List<HandlerMethodArgumentResolver> getDefaultInitBinderArgumentResolvers() {
		List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>(20);

		// Annotation-based argument resolution
		resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), false));
		resolvers.add(new RequestParamMapMethodArgumentResolver());
		resolvers.add(new PathVariableMethodArgumentResolver());
		resolvers.add(new PathVariableMapMethodArgumentResolver());
		resolvers.add(new MatrixVariableMethodArgumentResolver());
		resolvers.add(new MatrixVariableMapMethodArgumentResolver());
		resolvers.add(new ExpressionValueMethodArgumentResolver(getBeanFactory()));
		resolvers.add(new SessionAttributeMethodArgumentResolver());
		resolvers.add(new RequestAttributeMethodArgumentResolver());

		// Type-based argument resolution
		resolvers.add(new ServletRequestMethodArgumentResolver());
		resolvers.add(new ServletResponseMethodArgumentResolver());

		// Custom arguments
		if (getCustomArgumentResolvers() != null) {
			resolvers.addAll(getCustomArgumentResolvers());
		}

		// Catch-all
		resolvers.add(new PrincipalMethodArgumentResolver());
		resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), true));

		return resolvers;
	}

	Return the list of return value handlers to use including built-in and custom handlers provided via setReturnValueHandlers. /**
	 * Return the list of return value handlers to use including built-in and
	 * custom handlers provided via {@link #setReturnValueHandlers}.
	 */
	private List<HandlerMethodReturnValueHandler> getDefaultReturnValueHandlers() {
		List<HandlerMethodReturnValueHandler> handlers = new ArrayList<>(20);

		// Single-purpose return value types
		handlers.add(new ModelAndViewMethodReturnValueHandler());
		handlers.add(new ModelMethodProcessor());
		handlers.add(new ViewMethodReturnValueHandler());
		handlers.add(new ResponseBodyEmitterReturnValueHandler(getMessageConverters(),
				this.reactiveAdapterRegistry, this.taskExecutor, this.contentNegotiationManager));
		handlers.add(new StreamingResponseBodyReturnValueHandler());
		handlers.add(new HttpEntityMethodProcessor(getMessageConverters(),
				this.contentNegotiationManager, this.requestResponseBodyAdvice));
		handlers.add(new HttpHeadersReturnValueHandler());
		handlers.add(new CallableMethodReturnValueHandler());
		handlers.add(new DeferredResultMethodReturnValueHandler());
		handlers.add(new AsyncTaskMethodReturnValueHandler(this.beanFactory));

		// Annotation-based return value types
		handlers.add(new ServletModelAttributeMethodProcessor(false));
		handlers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(),
				this.contentNegotiationManager, this.requestResponseBodyAdvice));

		// Multi-purpose return value types
		handlers.add(new ViewNameMethodReturnValueHandler());
		handlers.add(new MapMethodProcessor());

		// Custom return value types
		if (getCustomReturnValueHandlers() != null) {
			handlers.addAll(getCustomReturnValueHandlers());
		}

		// Catch-all
		if (!CollectionUtils.isEmpty(getModelAndViewResolvers())) {
			handlers.add(new ModelAndViewResolverMethodReturnValueHandler(getModelAndViewResolvers()));
		}
		else {
			handlers.add(new ServletModelAttributeMethodProcessor(true));
		}

		return handlers;
	}


	Always return true since any method argument and return value type will be processed in some way. A method argument not recognized by any HandlerMethodArgumentResolver is interpreted as a request parameter if it is a simple type, or as a model attribute otherwise. A return value not recognized by any HandlerMethodReturnValueHandler will be interpreted as a model attribute. /**
	 * Always return {@code true} since any method argument and return value
	 * type will be processed in some way. A method argument not recognized
	 * by any HandlerMethodArgumentResolver is interpreted as a request parameter
	 * if it is a simple type, or as a model attribute otherwise. A return value
	 * not recognized by any HandlerMethodReturnValueHandler will be interpreted
	 * as a model attribute.
	 */
	@Override
	protected boolean supportsInternal(HandlerMethod handlerMethod) {
		return true;
	}

	@Override
	protected ModelAndView handleInternal(HttpServletRequest request,
			HttpServletResponse response, HandlerMethod handlerMethod) throws Exception {

		ModelAndView mav;
		checkRequest(request);

		// Execute invokeHandlerMethod in synchronized block if required.
		if (this.synchronizeOnSession) {
			HttpSession session = request.getSession(false);
			if (session != null) {
				Object mutex = WebUtils.getSessionMutex(session);
				synchronized (mutex) {
					mav = invokeHandlerMethod(request, response, handlerMethod);
				}
			}
			else {
				// No HttpSession available -> no mutex necessary
				mav = invokeHandlerMethod(request, response, handlerMethod);
			}
		}
		else {
			// No synchronization on session demanded at all...
			mav = invokeHandlerMethod(request, response, handlerMethod);
		}

		if (!response.containsHeader(HEADER_CACHE_CONTROL)) {
			if (getSessionAttributesHandler(handlerMethod).hasSessionAttributes()) {
				applyCacheSeconds(response, this.cacheSecondsForSessionAttributeHandlers);
			}
			else {
				prepareResponse(response);
			}
		}

		return mav;
	}

	This implementation always returns -1. An @RequestMapping method can calculate the lastModified value, call WebRequest.checkNotModified(long), and return null if the result of that call is true. /**
	 * This implementation always returns -1. An {@code @RequestMapping} method can
	 * calculate the lastModified value, call {@link WebRequest#checkNotModified(long)},
	 * and return {@code null} if the result of that call is {@code true}.
	 */
	@Override
	protected long getLastModifiedInternal(HttpServletRequest request, HandlerMethod handlerMethod) {
		return -1;
	}


	Return the SessionAttributesHandler instance for the given handler type (never null). /**
	 * Return the {@link SessionAttributesHandler} instance for the given handler type
	 * (never {@code null}).
	 */
	private SessionAttributesHandler getSessionAttributesHandler(HandlerMethod handlerMethod) {
		return this.sessionAttributesHandlerCache.computeIfAbsent(
				handlerMethod.getBeanType(),
				type -> new SessionAttributesHandler(type, this.sessionAttributeStore));
	}

	Invoke the RequestMapping handler method preparing a ModelAndView if view resolution is required. 
See Also: createInvocableHandlerMethod(HandlerMethod)
Since: 4.2/**
	 * Invoke the {@link RequestMapping} handler method preparing a {@link ModelAndView}
	 * if view resolution is required.
	 * @since 4.2
	 * @see #createInvocableHandlerMethod(HandlerMethod)
	 */
	@Nullable
	protected ModelAndView invokeHandlerMethod(HttpServletRequest request,
			HttpServletResponse response, HandlerMethod handlerMethod) throws Exception {

		ServletWebRequest webRequest = new ServletWebRequest(request, response);
		try {
			WebDataBinderFactory binderFactory = getDataBinderFactory(handlerMethod);
			ModelFactory modelFactory = getModelFactory(handlerMethod, binderFactory);

			ServletInvocableHandlerMethod invocableMethod = createInvocableHandlerMethod(handlerMethod);
			if (this.argumentResolvers != null) {
				invocableMethod.setHandlerMethodArgumentResolvers(this.argumentResolvers);
			}
			if (this.returnValueHandlers != null) {
				invocableMethod.setHandlerMethodReturnValueHandlers(this.returnValueHandlers);
			}
			invocableMethod.setDataBinderFactory(binderFactory);
			invocableMethod.setParameterNameDiscoverer(this.parameterNameDiscoverer);

			ModelAndViewContainer mavContainer = new ModelAndViewContainer();
			mavContainer.addAllAttributes(RequestContextUtils.getInputFlashMap(request));
			modelFactory.initModel(webRequest, mavContainer, invocableMethod);
			mavContainer.setIgnoreDefaultModelOnRedirect(this.ignoreDefaultModelOnRedirect);

			AsyncWebRequest asyncWebRequest = WebAsyncUtils.createAsyncWebRequest(request, response);
			asyncWebRequest.setTimeout(this.asyncRequestTimeout);

			WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(request);
			asyncManager.setTaskExecutor(this.taskExecutor);
			asyncManager.setAsyncWebRequest(asyncWebRequest);
			asyncManager.registerCallableInterceptors(this.callableInterceptors);
			asyncManager.registerDeferredResultInterceptors(this.deferredResultInterceptors);

			if (asyncManager.hasConcurrentResult()) {
				Object result = asyncManager.getConcurrentResult();
				mavContainer = (ModelAndViewContainer) asyncManager.getConcurrentResultContext()[0];
				asyncManager.clearConcurrentResult();
				LogFormatUtils.traceDebug(logger, traceOn -> {
					String formatted = LogFormatUtils.formatValue(result, !traceOn);
					return "Resume with async result [" + formatted + "]";
				});
				invocableMethod = invocableMethod.wrapConcurrentResult(result);
			}

			invocableMethod.invokeAndHandle(webRequest, mavContainer);
			if (asyncManager.isConcurrentHandlingStarted()) {
				return null;
			}

			return getModelAndView(mavContainer, modelFactory, webRequest);
		}
		finally {
			webRequest.requestCompleted();
		}
	}

	Create a ServletInvocableHandlerMethod from the given HandlerMethod definition. 
Params: handlerMethod – the HandlerMethod definition
Returns: the corresponding ServletInvocableHandlerMethod (or custom subclass thereof)
Since: 4.2/**
	 * Create a {@link ServletInvocableHandlerMethod} from the given {@link HandlerMethod} definition.
	 * @param handlerMethod the {@link HandlerMethod} definition
	 * @return the corresponding {@link ServletInvocableHandlerMethod} (or custom subclass thereof)
	 * @since 4.2
	 */
	protected ServletInvocableHandlerMethod createInvocableHandlerMethod(HandlerMethod handlerMethod) {
		return new ServletInvocableHandlerMethod(handlerMethod);
	}

	private ModelFactory getModelFactory(HandlerMethod handlerMethod, WebDataBinderFactory binderFactory) {
		SessionAttributesHandler sessionAttrHandler = getSessionAttributesHandler(handlerMethod);
		Class<?> handlerType = handlerMethod.getBeanType();
		Set<Method> methods = this.modelAttributeCache.get(handlerType);
		if (methods == null) {
			methods = MethodIntrospector.selectMethods(handlerType, MODEL_ATTRIBUTE_METHODS);
			this.modelAttributeCache.put(handlerType, methods);
		}
		List<InvocableHandlerMethod> attrMethods = new ArrayList<>();
		// Global methods first
		this.modelAttributeAdviceCache.forEach((controllerAdviceBean, methodSet) -> {
			if (controllerAdviceBean.isApplicableToBeanType(handlerType)) {
				Object bean = controllerAdviceBean.resolveBean();
				for (Method method : methodSet) {
					attrMethods.add(createModelAttributeMethod(binderFactory, bean, method));
				}
			}
		});
		for (Method method : methods) {
			Object bean = handlerMethod.getBean();
			attrMethods.add(createModelAttributeMethod(binderFactory, bean, method));
		}
		return new ModelFactory(attrMethods, binderFactory, sessionAttrHandler);
	}

	private InvocableHandlerMethod createModelAttributeMethod(WebDataBinderFactory factory, Object bean, Method method) {
		InvocableHandlerMethod attrMethod = new InvocableHandlerMethod(bean, method);
		if (this.argumentResolvers != null) {
			attrMethod.setHandlerMethodArgumentResolvers(this.argumentResolvers);
		}
		attrMethod.setParameterNameDiscoverer(this.parameterNameDiscoverer);
		attrMethod.setDataBinderFactory(factory);
		return attrMethod;
	}

	private WebDataBinderFactory getDataBinderFactory(HandlerMethod handlerMethod) throws Exception {
		Class<?> handlerType = handlerMethod.getBeanType();
		Set<Method> methods = this.initBinderCache.get(handlerType);
		if (methods == null) {
			methods = MethodIntrospector.selectMethods(handlerType, INIT_BINDER_METHODS);
			this.initBinderCache.put(handlerType, methods);
		}
		List<InvocableHandlerMethod> initBinderMethods = new ArrayList<>();
		// Global methods first
		this.initBinderAdviceCache.forEach((controllerAdviceBean, methodSet) -> {
			if (controllerAdviceBean.isApplicableToBeanType(handlerType)) {
				Object bean = controllerAdviceBean.resolveBean();
				for (Method method : methodSet) {
					initBinderMethods.add(createInitBinderMethod(bean, method));
				}
			}
		});
		for (Method method : methods) {
			Object bean = handlerMethod.getBean();
			initBinderMethods.add(createInitBinderMethod(bean, method));
		}
		return createDataBinderFactory(initBinderMethods);
	}

	private InvocableHandlerMethod createInitBinderMethod(Object bean, Method method) {
		InvocableHandlerMethod binderMethod = new InvocableHandlerMethod(bean, method);
		if (this.initBinderArgumentResolvers != null) {
			binderMethod.setHandlerMethodArgumentResolvers(this.initBinderArgumentResolvers);
		}
		binderMethod.setDataBinderFactory(new DefaultDataBinderFactory(this.webBindingInitializer));
		binderMethod.setParameterNameDiscoverer(this.parameterNameDiscoverer);
		return binderMethod;
	}

	Template method to create a new InitBinderDataBinderFactory instance.
The default implementation creates a ServletRequestDataBinderFactory.
This can be overridden for custom ServletRequestDataBinder subclasses.
Params: binderMethods – @InitBinder methods
Throws: Exception – in case of invalid state or arguments
Returns: the InitBinderDataBinderFactory instance to use/**
	 * Template method to create a new InitBinderDataBinderFactory instance.
	 * <p>The default implementation creates a ServletRequestDataBinderFactory.
	 * This can be overridden for custom ServletRequestDataBinder subclasses.
	 * @param binderMethods {@code @InitBinder} methods
	 * @return the InitBinderDataBinderFactory instance to use
	 * @throws Exception in case of invalid state or arguments
	 */
	protected InitBinderDataBinderFactory createDataBinderFactory(List<InvocableHandlerMethod> binderMethods)
			throws Exception {

		return new ServletRequestDataBinderFactory(binderMethods, getWebBindingInitializer());
	}

	@Nullable
	private ModelAndView getModelAndView(ModelAndViewContainer mavContainer,
			ModelFactory modelFactory, NativeWebRequest webRequest) throws Exception {

		modelFactory.updateModel(webRequest, mavContainer);
		if (mavContainer.isRequestHandled()) {
			return null;
		}
		ModelMap model = mavContainer.getModel();
		ModelAndView mav = new ModelAndView(mavContainer.getViewName(), model, mavContainer.getStatus());
		if (!mavContainer.isViewReference()) {
			mav.setView((View) mavContainer.getView());
		}
		if (model instanceof RedirectAttributes) {
			Map<String, ?> flashAttributes = ((RedirectAttributes) model).getFlashAttributes();
			HttpServletRequest request = webRequest.getNativeRequest(HttpServletRequest.class);
			if (request != null) {
				RequestContextUtils.getOutputFlashMap(request).putAll(flashAttributes);
			}
		}
		return mav;
	}

}
Author:	Rossen Stoyanchev, Juergen Hoeller, Sebastien Deleuze
See Also:	HandlerMethodArgumentResolver HandlerMethodReturnValueHandler
Since:	3.1
See Also:	createInvocableHandlerMethod(HandlerMethod)
Since:	4.2
Params:	handlerMethod – the `HandlerMethod` definition
Returns:	the corresponding `ServletInvocableHandlerMethod` (or custom subclass thereof)
Since:	4.2
Params:	binderMethods – `@InitBinder` methods
Throws:	Exception – in case of invalid state or arguments
Returns:	the InitBinderDataBinderFactory instance to use
/

org.springframework/ spring-webmvc/ 5.3.3/ org/springframework/web/servlet/mvc/method/annotation/RequestMappingHandlerAdapter.java
