阅读全文

⭐⭐⭐ Spring Boot 项目实战	⭐⭐⭐ Spring Cloud 项目实战
《Dubbo 实现原理与源码解析 —— 精品合集》	《Netty 实现原理与源码解析 —— 精品合集》
《Spring 实现原理与源码解析 —— 精品合集》	《MyBatis 实现原理与源码解析 —— 精品合集》
《Spring MVC 实现原理与源码解析 —— 精品合集》	《数据库实体设计合集》
《Spring Boot 实现原理与源码解析 —— 精品合集》	《Java 面试题 + Java 学习指南》

摘要: 原创出处 https://www.jianshu.com/p/a266a676bf9d 「一颗懒能」欢迎转载，保留摘要，谢谢！

• 包名 org.springframework.web.reactive.config
• 介绍
• 接口 WebFluxConfigurer
• 类

---

---

包名 org.springframework.web.reactive.config

看一张diagram：

config.jpg

介绍

Spring WebFlux配置基础架构。 将此注释添加到@Configuration类中，从WebFluxConfigurationSupport导入Spring Web Reactive配置，例如：

@Configuration
@EnableWebFlux
@ComponentScan(basePackageClasses = MyConfiguration.class)
public class MyConfiguration {
}

接口 WebFluxConfigurer

定义了回调方法来自定义通过@EnableWebFlux来启用WebFlux应用程序的配置。

@Enablewebflux注释的配置类可以实现这个接口的调用，并提供一个定制默认配置的机会。考虑实现这个接口，并根据需要覆盖相关的方法。

default void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder)

配置如何解决响应请求的内容类型。

default void addCorsMappings(CorsRegistry registry)

配置交叉原点请求处理。

default void configurePathMatching(PathMatchConfigurer configurer)

配置路径匹配选项。 HandlerMappings与路径匹配选项。

default void addResourceHandlers(ResourceHandlerRegistry registry)

为服务静态资源添加资源处理程序。

default void configureArgumentResolvers(ArgumentResolverConfigurer configurer)

配置自定义控制器方法参数的解析器。

default void configureHttpMessageCodecs(ServerCodecConfigurer configurer)

配置自定义HTTP消息读取器和编写器或重写内置的。

default void addFormatters(FormatterRegistry registry)

添加自定义转换器和格式化程序，用于执行控制器方法参数的类型转换和格式化。

@Nullable default MessageCodesResolver getMessageCodesResolver()

供一个自定义MessageCodesResolver用于数据绑定，而不是DataBinder中默认创建的那个。

default void configureViewResolvers(ViewResolverRegistry registry)

配置视图解析以处理控制器方法的返回值，这些方法依赖于解析视图来呈现响应。默认情况下，所有的控制器方法都依赖于视图解析，除非使用@ responsebody或显式返回ResponseEntity。视图可以显式地指定为字符串返回值或隐式，例如void返回值。

类

org.springframework.web.reactive.config.CorsRegistration

协助创建映射到路径模式的CorsConfiguration实例。默认情况下，当最大时间设置为30分钟时，允许GET，HEAD和POST请求的所有来源，标题和凭证。

构造方法：

CorsRegistration(java.lang.String pathPattern) 创建一个新的CorsRegistration，允许指定路径的最大时间设置为1800秒（30分钟）的GET，HEAD和POST请求的所有来源，标题和凭证。 CORS配置应该适用的路径;支持精确的路径映射URI（如“/ admin”）以及Ant样式的路径模式（如“/ admin / **”）。

方法：

• allowCredentials(boolean allowCredentials) 是否支持用户凭据。
• allowedHeaders(java.lang.String... headers) 设置飞行前请求可以在实际请求中使用的标题列表。如果它是一个:cache - control、content - language、Expires、last - modified或Pragma，根据CORS规范，则不需要列出header名称。 默认情况下，所有标题都是允许的。
• allowedMethods(java.lang.String... methods) 设置允许的HTTP方法
• allowedOrigins(java.lang.String... origins) 设置允许的来源 特殊值“*”允许所有域，默认情况下所有的来源都是允许的。
• exposedHeaders(java.lang.String... headers) 设置“简单”标题以外的响应标题列表
• getCorsConfiguration()
• getPathPattern()
• maxAge(long maxAge) 配置客户端可以缓存飞行前请求响应的时间，以秒为单位。

org.springframework.web.reactive.config.CorsRegistry

CorsRegistry协助注册CorsConfiguration映射到路径模式。 为指定的路径模式启用跨域请求处理

方法：

• addMapping(java.lang.String pathPattern) 为指定的路径模式启用跨域请求处理。支持精确的路径映射URI（如“/ admin”）以及Ant样式的路径模式（如“/ admin / **”）。默认情况下，允许所有来源，所有标题，凭据和GET，HEAD和POST方法，并且最大时间设置为30分钟。
• protected java.util.Map<java.lang.String,CorsConfiguration> getCorsConfigurations()

private final List<CorsRegistration> registrations = new ArrayList<>();

public CorsRegistration addMapping(String pathPattern) {
    CorsRegistration registration = new CorsRegistration(pathPattern);
    this.registrations.add(registration);
    return registration;
}



protected Map<String, CorsConfiguration> getCorsConfigurations() {
    Map<String, CorsConfiguration> configs = new LinkedHashMap<>(this.registrations.size());
    for (CorsRegistration registration : this.registrations) {
        configs.put(registration.getPathPattern(), registration.getCorsConfiguration());
    }
    return configs;
}

org.springframework.web.reactive.config.PathMatchConfigurer

协助配置HandlerMapping的路径匹配选项。

方法

• isUseCaseSensitiveMatch()
• isUseTrailingSlashMatch() 是否与URL匹配，而不管是否存在尾部斜线。如果启用，映射到“/ users”的方法也匹配“/ users /”。 默认值是true。
• setUseCaseSensitiveMatch(java.lang.Boolean caseSensitiveMatch) 是否与网址匹配，而不考虑其情况。
• setUseTrailingSlashMatch(java.lang.Boolean trailingSlashMatch) 是否与URL匹配，而不管是否以斜杠结尾。

@Nullable
private Boolean trailingSlashMatch;


@Nullable
private Boolean caseSensitiveMatch;



public PathMatchConfigurer setUseCaseSensitiveMatch(Boolean caseSensitiveMatch) {
    this.caseSensitiveMatch = caseSensitiveMatch;
    return this;
}

public PathMatchConfigurer setUseTrailingSlashMatch(Boolean trailingSlashMatch) {
    this.trailingSlashMatch = trailingSlashMatch;
    return this;
}

@Nullable
protected Boolean isUseTrailingSlashMatch() {
    return this.trailingSlashMatch;
}

@Nullable
protected Boolean isUseCaseSensitiveMatch() {
    return this.caseSensitiveMatch;
}

org.springframework.web.reactive.config.ResourceChainRegistration

协助完成资源和转换器的注册

构造器

• ResourceChainRegistration(boolean cacheResources)
• ResourceChainRegistration(boolean cacheResources)

方法

• addResolver(ResourceResolver resolver) 将一个资源解析器添加到链中。
• addTransformer(ResourceTransformer transformer) 向链中添加资源转换器器。
• getResourceResolvers()
• getResourceTransformers()

private static final String DEFAULT_CACHE_NAME = "spring-resource-chain-cache";

private static final boolean isWebJarsAssetLocatorPresent = ClassUtils.isPresent(
        "org.webjars.WebJarAssetLocator", ResourceChainRegistration.class.getClassLoader());


private final List<ResourceResolver> resolvers = new ArrayList<>(4);

private final List<ResourceTransformer> transformers = new ArrayList<>(4);

private boolean hasVersionResolver;

private boolean hasPathResolver;

private boolean hasCssLinkTransformer;

private boolean hasWebjarsResolver;

    public ResourceChainRegistration(boolean cacheResources) {
    this(cacheResources, cacheResources ? new ConcurrentMapCache(DEFAULT_CACHE_NAME) : null);
}

public ResourceChainRegistration(boolean cacheResources, @Nullable Cache cache) {
    Assert.isTrue(!cacheResources || cache != null, "'cache' is required when cacheResources=true");
    if (cacheResources) {
        this.resolvers.add(new CachingResourceResolver(cache));
        this.transformers.add(new CachingResourceTransformer(cache));
    }
}



public ResourceChainRegistration addResolver(ResourceResolver resolver) {
    Assert.notNull(resolver, "The provided ResourceResolver should not be null");
    this.resolvers.add(resolver);
    if (resolver instanceof VersionResourceResolver) {
        this.hasVersionResolver = true;
    }
    else if (resolver instanceof PathResourceResolver) {
        this.hasPathResolver = true;
    }
    else if (resolver instanceof WebJarsResourceResolver) {
        this.hasWebjarsResolver = true;
    }
    return this;
}



public ResourceChainRegistration addTransformer(ResourceTransformer transformer) {
    Assert.notNull(transformer, "The provided ResourceTransformer should not be null");
    this.transformers.add(transformer);
    if (transformer instanceof CssLinkResourceTransformer) {
        this.hasCssLinkTransformer = true;
    }
    return this;
}



protected List<ResourceResolver> getResourceResolvers() {
    if (!this.hasPathResolver) {
        List<ResourceResolver> result = new ArrayList<>(this.resolvers);
        if (isWebJarsAssetLocatorPresent && !this.hasWebjarsResolver) {
            result.add(new WebJarsResourceResolver());
        }
        result.add(new PathResourceResolver());
        return result;
    }
    return this.resolvers;
}

protected List<ResourceTransformer> getResourceTransformers() {
    if (this.hasVersionResolver && !this.hasCssLinkTransformer) {
        List<ResourceTransformer> result = new ArrayList<>(this.transformers);
        boolean hasTransformers = !this.transformers.isEmpty();
        boolean hasCaching = hasTransformers && this.transformers.get(0) instanceof CachingResourceTransformer;
        result.add(hasCaching ? 1 : 0, new CssLinkResourceTransformer());
        return result;
    }
    return this.transformers;
}

org.springframework.web.reactive.config.ResourceHandlerRegistry

通过Spring WebFlux存储资源处理程序的注册，以提供静态资源（如图像，css文件和其他），包括设置优化的高速缓存头，以便在Web浏览器中进行高效加载。资源可以从Web应用程序根目录下的位置，类路径和其他位置提供。

要创建资源处理程序，请使用addResourceHandler（String ...）提供应为其调用处理程序以提供静态资源（例如“/ resources / **”）的URL路径模式。

然后在返回的ResourceHandlerRegistration上使用其他方法来添加一个或多个从（例如{“/”，“classpath：/ META-INF / public-web-resources /”}）静态内容的位置，或者指定一个缓存期间服务的资源。

构造器

• ResourceHandlerRegistry(ResourceLoader resourceLoader) 为给定资源加载器（通常是应用程序上下文）创建新的资源处理程序注册表。
• ​

方法

• addResourceHandler(java.lang.String... patterns) 添加一个资源处理程序，用于根据指定的URL路径模式提供静态资源。 处理程序将针对每个与指定路径模式匹配的传入请求进行调用。像“/static/ **”或“/css/{filename:\w+.css}”的模式是允许的。有关语法的更多详细信息，请参阅PathPattern。
• getHandlerMapping() 返回映射资源处理程序的处理程序映射;或者在没有注册的情况下为空。
• hasMappingForPattern(java.lang.String pathPattern) 资源处理程序是否已经注册了给定的路径模式。
• setOrder(int order) 指定相对于Spring配置中配置的其他HandlerMappings进行资源处理的顺序。 使用的默认值是Integer.MAX_VALUE-1。

private final ResourceLoader resourceLoader;

private final List<ResourceHandlerRegistration> registrations = new ArrayList<>();

private int order = Integer.MAX_VALUE -1;

public ResourceHandlerRegistry(ResourceLoader resourceLoader) {
    this.resourceLoader = resourceLoader;
}

public ResourceHandlerRegistration addResourceHandler(String... patterns) {
    ResourceHandlerRegistration registration = new ResourceHandlerRegistration(this.resourceLoader, patterns);
    this.registrations.add(registration);
    return registration;
}

public boolean hasMappingForPattern(String pathPattern) {
    for (ResourceHandlerRegistration registration : this.registrations) {
        if (Arrays.asList(registration.getPathPatterns()).contains(pathPattern)) {
            return true;
        }
    }
    return false;
}


public ResourceHandlerRegistry setOrder(int order) {
    this.order = order;
    return this;
}

@Nullable
protected AbstractUrlHandlerMapping getHandlerMapping() {
    if (this.registrations.isEmpty()) {
        return null;
    }
    Map<String, WebHandler> urlMap = new LinkedHashMap<>();
    for (ResourceHandlerRegistration registration : this.registrations) {
        for (String pathPattern : registration.getPathPatterns()) {
            ResourceWebHandler handler = registration.getRequestHandler();
            try {
                handler.afterPropertiesSet();
            }
            catch (Throwable ex) {
                throw new BeanInitializationException("Failed to init ResourceHttpRequestHandler", ex);
            }
            urlMap.put(pathPattern, handler);
        }
    }
    SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
    handlerMapping.setOrder(this.order);
    handlerMapping.setUrlMap(urlMap);
    return handlerMapping;
}

org.springframework.web.reactive.config.ResourceHandlerRegistration

协助创建和配置静态资源处理程序。

构造器

• ResourceHandlerRegistration(ResourceLoader resourceLoader, java.lang.String... pathPatterns) 创建一个ResourceHandlerRegistration实例。
  • resourceLoader ：用于将字符串位置转换为资源的资源加载器
  • pathPatterns - 一个或多个资源URL路径模式

方法

• addResourceLocations(java.lang.String... resourceLocations)
  • 添加一个或多个资源位置来服务静态内容。每个位置必须指向一个有效的目录。多个位置可以指定为逗号分隔的列表，并且位置将按照指定的顺序对给定的资源进行检查。
  • 例如，{“/”，“classpath：/ META-INF / public-web-resources /”}允许资源从Web应用程序的根目录和任何包含/ META-INF / public-web-resources /的目录，Web应用程序根目录中的资源优先。
• getPathPatterns()
• getRequestHandler()
• resourceChain(boolean cacheResources)
• resourceChain(boolean cacheResources, Cache cache)
• setCacheControl(CacheControl cacheControl) 指定应该由资源处理程序使用的CacheControl。

private final ResourceLoader resourceLoader;

private final String[] pathPatterns;

private final List<Resource> locations = new ArrayList<>();

@Nullable
private CacheControl cacheControl;

@Nullable
private ResourceChainRegistration resourceChainRegistration;

public ResourceHandlerRegistration(ResourceLoader resourceLoader, String... pathPatterns) {
    Assert.notNull(resourceLoader, "ResourceLoader is required");
    Assert.notEmpty(pathPatterns, "At least one path pattern is required for resource handling");
    this.resourceLoader = resourceLoader;
    this.pathPatterns = pathPatterns;
}

public ResourceHandlerRegistration addResourceLocations(String... resourceLocations) {
    for (String location : resourceLocations) {
        this.locations.add(this.resourceLoader.getResource(location));
    }
    return this;
}



public ResourceHandlerRegistration setCacheControl(CacheControl cacheControl) {
    this.cacheControl = cacheControl;
    return this;
}

public ResourceChainRegistration resourceChain(boolean cacheResources) {
    this.resourceChainRegistration = new ResourceChainRegistration(cacheResources);
    return this.resourceChainRegistration;
}

public ResourceChainRegistration resourceChain(boolean cacheResources, Cache cache) {
    this.resourceChainRegistration = new ResourceChainRegistration(cacheResources, cache);
    return this.resourceChainRegistration;
}


protected String[] getPathPatterns() {
    return this.pathPatterns;
}


protected ResourceWebHandler getRequestHandler() {
    ResourceWebHandler handler = new ResourceWebHandler();
    if (this.resourceChainRegistration != null) {
        handler.setResourceResolvers(this.resourceChainRegistration.getResourceResolvers());
        handler.setResourceTransformers(this.resourceChainRegistration.getResourceTransformers());
    }
    handler.setLocations(this.locations);
    if (this.cacheControl != null) {
        handler.setCacheControl(this.cacheControl);
    }
    return handler;
}

org.springframework.web.reactive.config.UrlBasedViewResolverRegistration

协助配置UrlBasedViewResolver的属性。

构造器

• UrlBasedViewResolverRegistration(UrlBasedViewResolver viewResolver)

方法

• getViewResolver()
• prefix(java.lang.String prefix) 设置在构建URL时附加到视图名称的前缀。
• suffix(java.lang.String suffix) 设置在构建URL时附加到视图名称的后缀。
• viewClass(java.lang.Class<?> viewClass) 设置应该用于创建视图的视图类。
• viewNames(java.lang.String... viewNames) 设置可由该视图解析器处理的视图名称（或名称模式）。视图名称可以包含简单的通配符，这样'my '，' Report'和'* Repo *'将全部匹配视图名称'myReport'。
• ​

private final UrlBasedViewResolver viewResolver;


public UrlBasedViewResolverRegistration(UrlBasedViewResolver viewResolver) {
    Assert.notNull(viewResolver, "ViewResolver must not be null");
    this.viewResolver = viewResolver;
}

public UrlBasedViewResolverRegistration prefix(String prefix) {
    this.viewResolver.setPrefix(prefix);
    return this;
}

public UrlBasedViewResolverRegistration suffix(String suffix) {
    this.viewResolver.setSuffix(suffix);
    return this;
}


public UrlBasedViewResolverRegistration viewClass(Class<?> viewClass) {
    this.viewResolver.setViewClass(viewClass);
    return this;
}


public UrlBasedViewResolverRegistration viewNames(String... viewNames) {
    this.viewResolver.setViewNames(viewNames);
    return this;
}

protected UrlBasedViewResolver getViewResolver() {
    return this.viewResolver;
}

org.springframework.web.reactive.config.ViewResolverRegistry

协助配置一个ViewResolver的链，支持不同的模板机制。另外，还可以根据所请求的内容类型配置defaultView以进行渲染，例如， JSON，XML等

构造器

• ViewResolverRegistry(ApplicationContext applicationContext)
• ​

方法

• defaultViews(View... defaultViews) 设置与任何视图名称关联的默认视图，并根据请求的内容类型的最佳匹配进行选择。使用HttpMessageWriterView来调整和使用任何现有的HttpMessageWriter（例如JSON，XML）作为一个视图。
• freeMarker() 注册一个带有“.ftl”后缀的FreeMarkerViewResolver。
• getDefaultViews()
• getOrder()
• getViewResolvers()
• hasRegistrations() 是否有任何视图解析器已被注册。
• order(int order) 设置ViewResolutionResultHandler的顺序。 默认情况下，此属性未设置，这意味着结果处理程序将按顺序排列。
• viewResolver(ViewResolver viewResolver) 注册一个ViewResolver bean实例。这可能有助于配置第三方解析器实现，或者在这个类中不公开一些需要设置的高级属性时，可以替代其他注册方法。
• ​

@Nullable
private final ApplicationContext applicationContext;

private final List<ViewResolver> viewResolvers = new ArrayList<>(4);

private final List<View> defaultViews = new ArrayList<>(4);


@Nullable
private Integer order;

public ViewResolverRegistry(@Nullable ApplicationContext applicationContext) {
    this.applicationContext = applicationContext;
}

public UrlBasedViewResolverRegistration freeMarker() {
    if (!checkBeanOfType(FreeMarkerConfigurer.class)) {
        throw new BeanInitializationException("In addition to a FreeMarker view resolver " +
                "there must also be a single FreeMarkerConfig bean in this web application context " +
                "(or its parent): FreeMarkerConfigurer is the usual implementation. " +
                "This bean may be given any name.");
    }
    FreeMarkerRegistration registration = new FreeMarkerRegistration();
    UrlBasedViewResolver resolver = registration.getViewResolver();
    if (this.applicationContext != null) {
        resolver.setApplicationContext(this.applicationContext);
    }
    this.viewResolvers.add(resolver);
    return registration;
}

public void viewResolver(ViewResolver viewResolver) {
    this.viewResolvers.add(viewResolver);
}

public void defaultViews(View... defaultViews) {
    this.defaultViews.addAll(Arrays.asList(defaultViews));
}


public boolean hasRegistrations() {
    return (!this.viewResolvers.isEmpty());
}

public void order(int order) {
    this.order = order;
}

private boolean checkBeanOfType(Class<?> beanType) {
    return (this.applicationContext == null ||
            !ObjectUtils.isEmpty(BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
                    this.applicationContext, beanType, false, false)));
}

protected int getOrder() {
    return (this.order != null ? this.order : Ordered.LOWEST_PRECEDENCE);
}

protected List<ViewResolver> getViewResolvers() {
    return this.viewResolvers;
}

protected List<View> getDefaultViews() {
    return this.defaultViews;
}


private static class FreeMarkerRegistration extends UrlBasedViewResolverRegistration {

    public FreeMarkerRegistration() {
        super(new FreeMarkerViewResolver());
        getViewResolver().setSuffix(".ftl");
    }
}

org.springframework.web.reactive.config.WebFluxConfigurationSupport

所有实现的接口

Aware, ApplicationContextAware

Spring WebFlux配置的主要类。直接导入或扩展和重写受保护的方法来自定义。

@Nullable
    private Map<String, CorsConfiguration> corsConfigurations;

    @Nullable
    private PathMatchConfigurer pathMatchConfigurer;

    @Nullable
    private ViewResolverRegistry viewResolverRegistry;

    @Nullable
    private ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(@Nullable ApplicationContext applicationContext) {
        this.applicationContext = applicationContext;
    }

    @Nullable
    public final ApplicationContext getApplicationContext() {
        return this.applicationContext;
    }


    @Bean
    public DispatcherHandler webHandler() {
        return new DispatcherHandler();
    }

    @Bean
    @Order(0)
    public WebExceptionHandler responseStatusExceptionHandler() {
        return new ResponseStatusExceptionHandler();
    }

    @Bean
    public RequestMappingHandlerMapping requestMappingHandlerMapping() {
        RequestMappingHandlerMapping mapping = createRequestMappingHandlerMapping();
        mapping.setOrder(0);
        mapping.setContentTypeResolver(webFluxContentTypeResolver());
        mapping.setCorsConfigurations(getCorsConfigurations());

        PathMatchConfigurer configurer = getPathMatchConfigurer();
        Boolean useTrailingSlashMatch = configurer.isUseTrailingSlashMatch();
        Boolean useCaseSensitiveMatch = configurer.isUseCaseSensitiveMatch();
        if (useTrailingSlashMatch != null) {
            mapping.setUseTrailingSlashMatch(useTrailingSlashMatch);
        }
        if (useCaseSensitiveMatch != null) {
            mapping.setUseCaseSensitiveMatch(useCaseSensitiveMatch);
        }
        return mapping;
    }

    protected RequestMappingHandlerMapping createRequestMappingHandlerMapping() {
        return new RequestMappingHandlerMapping();
    }

    @Bean
    public RequestedContentTypeResolver webFluxContentTypeResolver() {
        RequestedContentTypeResolverBuilder builder = new RequestedContentTypeResolverBuilder();
        configureContentTypeResolver(builder);
        return builder.build();
    }
    protected void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder) {
    }



    protected final Map<String, CorsConfiguration> getCorsConfigurations() {
        if (this.corsConfigurations == null) {
            CorsRegistry registry = new CorsRegistry();
            addCorsMappings(registry);
            this.corsConfigurations = registry.getCorsConfigurations();
        }
        return this.corsConfigurations;
    }

    protected void addCorsMappings(CorsRegistry registry) {
    }

    protected final PathMatchConfigurer getPathMatchConfigurer() {
        if (this.pathMatchConfigurer == null) {
            this.pathMatchConfigurer = new PathMatchConfigurer();
            configurePathMatching(this.pathMatchConfigurer);
        }
        return this.pathMatchConfigurer;
    }

    public void configurePathMatching(PathMatchConfigurer configurer) {
    }

    @Bean
    public RouterFunctionMapping routerFunctionMapping() {
        RouterFunctionMapping mapping = createRouterFunctionMapping();
        mapping.setOrder(-1); // go before RequestMappingHandlerMapping
        mapping.setMessageReaders(serverCodecConfigurer().getReaders());
        mapping.setCorsConfigurations(getCorsConfigurations());

        return mapping;
    }

    @Bean
    public HandlerMapping resourceHandlerMapping() {
        ResourceLoader resourceLoader = this.applicationContext;
        if (resourceLoader == null) {
            resourceLoader = new DefaultResourceLoader();
        }
        ResourceHandlerRegistry registry = new ResourceHandlerRegistry(resourceLoader);
        addResourceHandlers(registry);

        AbstractHandlerMapping handlerMapping = registry.getHandlerMapping();
        if (handlerMapping != null) {
            PathMatchConfigurer configurer = getPathMatchConfigurer();
            Boolean useTrailingSlashMatch = configurer.isUseTrailingSlashMatch();
            Boolean useCaseSensitiveMatch = configurer.isUseCaseSensitiveMatch();
            if (useTrailingSlashMatch != null) {
                handlerMapping.setUseTrailingSlashMatch(useTrailingSlashMatch);
            }
            if (useCaseSensitiveMatch != null) {
                handlerMapping.setUseCaseSensitiveMatch(useCaseSensitiveMatch);
            }
        }
        else {
            handlerMapping = new EmptyHandlerMapping();
        }
        return handlerMapping;
    }

    ...

org.springframework.web.reactive.config.WebFluxConfigurerComposite

所有实现的接口

WebFluxConfigurer

将WebFluxConfigurer委托给一个或多个。

    public class WebFluxConfigurerComposite implements WebFluxConfigurer {

    private final List<WebFluxConfigurer> delegates = new ArrayList<>();


    public void addWebFluxConfigurers(List<WebFluxConfigurer> configurers) {
        if (!CollectionUtils.isEmpty(configurers)) {
            this.delegates.addAll(configurers);
        }
    }


    @Override
    public void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder) {
        this.delegates.forEach(delegate -> delegate.configureContentTypeResolver(builder));
    }

    @Override
    public void addCorsMappings(CorsRegistry registry) {
        this.delegates.forEach(delegate -> delegate.addCorsMappings(registry));
    }

    @Override
    public void configurePathMatching(PathMatchConfigurer configurer) {
        this.delegates.forEach(delegate -> delegate.configurePathMatching(configurer));
    }

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        this.delegates.forEach(delegate -> delegate.addResourceHandlers(registry));
    }

    @Override
    public void configureArgumentResolvers(ArgumentResolverConfigurer configurer) {
        this.delegates.forEach(delegate -> delegate.configureArgumentResolvers(configurer));
    }

    @Override
    public void configureHttpMessageCodecs(ServerCodecConfigurer configurer) {
        this.delegates.forEach(delegate -> delegate.configureHttpMessageCodecs(configurer));
    }

    @Override
    public void addFormatters(FormatterRegistry registry) {
        this.delegates.forEach(delegate -> delegate.addFormatters(registry));
    }

    @Override
    public Validator getValidator() {
        return createSingleBean(WebFluxConfigurer::getValidator, Validator.class);
    }

    @Override
    public MessageCodesResolver getMessageCodesResolver() {
        return createSingleBean(WebFluxConfigurer::getMessageCodesResolver, MessageCodesResolver.class);
    }

    @Override
    public void configureViewResolvers(ViewResolverRegistry registry) {
        this.delegates.forEach(delegate -> delegate.configureViewResolvers(registry));
    }

    @Nullable
    private <T> T createSingleBean(Function<WebFluxConfigurer, T> factory, Class<T> beanType) {
        List<T> result = this.delegates.stream().map(factory).filter(t -> t != null).collect(Collectors.toList());
        if (result.isEmpty()) {
            return null;
        }
        else if (result.size() == 1) {
            return result.get(0);
        }
        else {
            throw new IllegalStateException("More than one WebFluxConfigurer implements " +
                    beanType.getSimpleName() + " factory method.");
        }
    }

}

org.springframework.web.reactive.config.DelegatingWebFluxConfiguration

• java.lang.Object
  • org.springframework.web.reactive.config.WebFluxConfigurationSupport
    • org.springframework.web.reactive.config.DelegatingWebFluxConfiguration

WebFluxConfigurationSupport的一个子类，用于检测并委托所有类型为WebFluxConfigurer的bean，允许它们自定义由WebFluxConfigurationSupport提供的配置。这是由@EnableWebFlux实际导入的类。

@Configuration
public class DelegatingWebFluxConfiguration extends WebFluxConfigurationSupport {

    private final WebFluxConfigurerComposite configurers = new WebFluxConfigurerComposite();

    @Autowired(required = false)
    public void setConfigurers(List<WebFluxConfigurer> configurers) {
        if (!CollectionUtils.isEmpty(configurers)) {
            this.configurers.addWebFluxConfigurers(configurers);
        }
    }

    @Override
    protected void configureContentTypeResolver(RequestedContentTypeResolverBuilder builder) {
        this.configurers.configureContentTypeResolver(builder);
    }

    @Override
    protected void addCorsMappings(CorsRegistry registry) {
        this.configurers.addCorsMappings(registry);
    }

    @Override
    public void configurePathMatching(PathMatchConfigurer configurer) {
        this.configurers.configurePathMatching(configurer);
    }

    @Override
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        this.configurers.addResourceHandlers(registry);
    }

    @Override
    protected void configureArgumentResolvers(ArgumentResolverConfigurer configurer) {
        this.configurers.configureArgumentResolvers(configurer);
    }

    @Override
    protected void configureHttpMessageCodecs(ServerCodecConfigurer configurer) {
        this.configurers.configureHttpMessageCodecs(configurer);
    }

    @Override
    protected void addFormatters(FormatterRegistry registry) {
        this.configurers.addFormatters(registry);
    }

    @Override
    protected Validator getValidator() {
        Validator validator = this.configurers.getValidator();
        return (validator != null ? validator : super.getValidator());
    }

    @Override
    protected MessageCodesResolver getMessageCodesResolver() {
        MessageCodesResolver messageCodesResolver = this.configurers.getMessageCodesResolver();
        return (messageCodesResolver != null ? messageCodesResolver : super.getMessageCodesResolver());
    }

    @Override
    protected void configureViewResolvers(ViewResolverRegistry registry) {
        this.configurers.configureViewResolvers(registry);
    }
}

666. 彩蛋

如果你对 Spring Webflux 感兴趣，欢迎加入我的知识星球一起交流。