说在前面
本次开始spring-boot-autoconfigure源码解析之WebMvcAutoConfiguration
源码解析
@Configuration
@ConditionalOnWebApplication
@ConditionalOnClass({ Servlet.class, DispatcherServlet.class,
WebMvcConfigurerAdapter.class })
@ConditionalOnMissingBean(WebMvcConfigurationSupport.class)
@AutoConfigureOrder(Ordered.HIGHEST_PRECEDENCE + 10)
@AutoConfigureAfter({ DispatcherServletAutoConfiguration.class,
ValidationAutoConfiguration.class })
public class WebMvcAutoConfiguration {
public static final String DEFAULT_PREFIX = "";
public static final String DEFAULT_SUFFIX = "";
@Bean
@ConditionalOnMissingBean(HiddenHttpMethodFilter.class)
public OrderedHiddenHttpMethodFilter hiddenHttpMethodFilter() {
return new OrderedHiddenHttpMethodFilter();
}
@Bean
@ConditionalOnMissingBean(HttpPutFormContentFilter.class)
@ConditionalOnProperty(prefix = "spring.mvc.formcontent.putfilter", name = "enabled", matchIfMissing = true)
public OrderedHttpPutFormContentFilter httpPutFormContentFilter() {
return new OrderedHttpPutFormContentFilter();
}
// Defined as a nested config to ensure WebMvcConfigurerAdapter is not read when not 定义为嵌套配置，以确保不读取WebMvcConfigurerAdapter
// on the classpath 在类路径中
@Configuration
@Import(EnableWebMvcConfiguration.class)
@EnableConfigurationProperties({ WebMvcProperties.class, ResourceProperties.class })
public static class WebMvcAutoConfigurationAdapter extends WebMvcConfigurerAdapter {
private static final Log logger = LogFactory
.getLog(WebMvcConfigurerAdapter.class);
private final ResourceProperties resourceProperties;
private final WebMvcProperties mvcProperties;
private final ListableBeanFactory beanFactory;
private final HttpMessageConverters messageConverters;
final ResourceHandlerRegistrationCustomizer resourceHandlerRegistrationCustomizer;
public WebMvcAutoConfigurationAdapter(ResourceProperties resourceProperties,
WebMvcProperties mvcProperties, ListableBeanFactory beanFactory,
@Lazy HttpMessageConverters messageConverters,
ObjectProvider<ResourceHandlerRegistrationCustomizer> resourceHandlerRegistrationCustomizerProvider) {
this.resourceProperties = resourceProperties;
this.mvcProperties = mvcProperties;
this.beanFactory = beanFactory;
this.messageConverters = messageConverters;
this.resourceHandlerRegistrationCustomizer = resourceHandlerRegistrationCustomizerProvider
.getIfAvailable();
}
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
converters.addAll(this.messageConverters.getConverters());
}
@Override
public void configureAsyncSupport(AsyncSupportConfigurer configurer) {
Long timeout = this.mvcProperties.getAsync().getRequestTimeout();
if (timeout != null) {
configurer.setDefaultTimeout(timeout);
}
}
@Override
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
Map<String, MediaType> mediaTypes = this.mvcProperties.getMediaTypes();
for (Entry<String, MediaType> mediaType : mediaTypes.entrySet()) {
configurer.mediaType(mediaType.getKey(), mediaType.getValue());
}
}
// 初始化InternalResourceViewResolver
@Bean
@ConditionalOnMissingBean
public InternalResourceViewResolver defaultViewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix(this.mvcProperties.getView().getPrefix());
resolver.setSuffix(this.mvcProperties.getView().getSuffix());
return resolver;
}
// 初始化BeanNameViewResolver
@Bean
@ConditionalOnBean(View.class)
@ConditionalOnMissingBean
public BeanNameViewResolver beanNameViewResolver() {
BeanNameViewResolver resolver = new BeanNameViewResolver();
resolver.setOrder(Ordered.LOWEST_PRECEDENCE - 10);
return resolver;
}
// 初始化ContentNegotiatingViewResolver
@Bean
@ConditionalOnBean(ViewResolver.class)
@ConditionalOnMissingBean(name = "viewResolver", value = ContentNegotiatingViewResolver.class)
public ContentNegotiatingViewResolver viewResolver(BeanFactory beanFactory) {
ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
resolver.setContentNegotiationManager(
beanFactory.getBean(ContentNegotiationManager.class));
// ContentNegotiatingViewResolver uses all the other view resolvers to locate contentatingviewresolver使用所有其他视图解析器来定位
// a view so it should have a high precedence 一个视图，因此它应该具有较高的优先级
resolver.setOrder(Ordered.HIGHEST_PRECEDENCE);
return resolver;
}
@Bean
@ConditionalOnMissingBean
@ConditionalOnProperty(prefix = "spring.mvc", name = "locale")
public LocaleResolver localeResolver() {
if (this.mvcProperties
.getLocaleResolver() == WebMvcProperties.LocaleResolver.FIXED) {
return new FixedLocaleResolver(this.mvcProperties.getLocale());
}
AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver();
localeResolver.setDefaultLocale(this.mvcProperties.getLocale());
return localeResolver;
}
@Bean
@ConditionalOnProperty(prefix = "spring.mvc", name = "date-format")
public Formatter<Date> dateFormatter() {
return new DateFormatter(this.mvcProperties.getDateFormat());
}
@Override
public MessageCodesResolver getMessageCodesResolver() {
if (this.mvcProperties.getMessageCodesResolverFormat() != null) {
DefaultMessageCodesResolver resolver = new DefaultMessageCodesResolver();
resolver.setMessageCodeFormatter(
this.mvcProperties.getMessageCodesResolverFormat());
return resolver;
}
return null;
}
@Override
public void addFormatters(FormatterRegistry registry) {
for (Converter<?, ?> converter : getBeansOfType(Converter.class)) {
registry.addConverter(converter);
}
for (GenericConverter converter : getBeansOfType(GenericConverter.class)) {
registry.addConverter(converter);
}
for (Formatter<?> formatter : getBeansOfType(Formatter.class)) {
registry.addFormatter(formatter);
}
}
private <T> Collection<T> getBeansOfType(Class<T> type) {
return this.beanFactory.getBeansOfType(type).values();
}
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
if (!this.resourceProperties.isAddMappings()) {
logger.debug("Default resource handling disabled");
return;
}
Integer cachePeriod = this.resourceProperties.getCachePeriod();
if (!registry.hasMappingForPattern("/webjars/**")) {
customizeResourceHandlerRegistration(registry
.addResourceHandler("/webjars/**")
.addResourceLocations("classpath:/META-INF/resources/webjars/")
.setCachePeriod(cachePeriod));
}
String staticPathPattern = this.mvcProperties.getStaticPathPattern();
if (!registry.hasMappingForPattern(staticPathPattern)) {
customizeResourceHandlerRegistration(
registry.addResourceHandler(staticPathPattern)
.addResourceLocations(
this.resourceProperties.getStaticLocations())
.setCachePeriod(cachePeriod));
}
}
@Bean
public WelcomePageHandlerMapping welcomePageHandlerMapping(
ResourceProperties resourceProperties) {
return new WelcomePageHandlerMapping(resourceProperties.getWelcomePage(),
this.mvcProperties.getStaticPathPattern());
}
private void customizeResourceHandlerRegistration(
ResourceHandlerRegistration registration) {
if (this.resourceHandlerRegistrationCustomizer != null) {
this.resourceHandlerRegistrationCustomizer.customize(registration);
}
}
@Bean
@ConditionalOnMissingBean({ RequestContextListener.class,
RequestContextFilter.class })
public static RequestContextFilter requestContextFilter() {
return new OrderedRequestContextFilter();
}
@Configuration
@ConditionalOnProperty(value = "spring.mvc.favicon.enabled", matchIfMissing = true)
public static class FaviconConfiguration {
private final ResourceProperties resourceProperties;
public FaviconConfiguration(ResourceProperties resourceProperties) {
this.resourceProperties = resourceProperties;
}
// 初始化SimpleUrlHandlerMapping
@Bean
public SimpleUrlHandlerMapping faviconHandlerMapping() {
SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
mapping.setOrder(Ordered.HIGHEST_PRECEDENCE + 1);
mapping.setUrlMap(Collections.singletonMap("**/favicon.ico",
faviconRequestHandler()));
return mapping;
}
@Bean
public ResourceHttpRequestHandler faviconRequestHandler() {
ResourceHttpRequestHandler requestHandler = new ResourceHttpRequestHandler();
requestHandler
.setLocations(this.resourceProperties.getFaviconLocations());
return requestHandler;
}
}
}
/**
* Configuration equivalent to {@code @EnableWebMvc}.
*/
@Configuration
public static class EnableWebMvcConfiguration extends DelegatingWebMvcConfiguration {
private final WebMvcProperties mvcProperties;
private final ListableBeanFactory beanFactory;
private final WebMvcRegistrations mvcRegistrations;
public EnableWebMvcConfiguration(
ObjectProvider<WebMvcProperties> mvcPropertiesProvider,
ObjectProvider<WebMvcRegistrations> mvcRegistrationsProvider,
ListableBeanFactory beanFactory) {
this.mvcProperties = mvcPropertiesProvider.getIfAvailable();
this.mvcRegistrations = mvcRegistrationsProvider.getIfUnique();
this.beanFactory = beanFactory;
}
// 创建RequestMappingHandlerAdapter
@Bean
@Override
public RequestMappingHandlerAdapter requestMappingHandlerAdapter() {
RequestMappingHandlerAdapter adapter = super.requestMappingHandlerAdapter();
adapter.setIgnoreDefaultModelOnRedirect((this.mvcProperties != null)
? this.mvcProperties.isIgnoreDefaultModelOnRedirect() : true);
return adapter;
}
@Override
protected RequestMappingHandlerAdapter createRequestMappingHandlerAdapter() {
if (this.mvcRegistrations != null
&& this.mvcRegistrations.getRequestMappingHandlerAdapter() != null) {
return this.mvcRegistrations.getRequestMappingHandlerAdapter();
}
return super.createRequestMappingHandlerAdapter();
}
// 创建RequestMappingHandlerMapping
@Bean
@Primary
@Override
public RequestMappingHandlerMapping requestMappingHandlerMapping() {
// Must be @Primary for MvcUriComponentsBuilder to work
return super.requestMappingHandlerMapping();
}
// 创建Validator
@Bean
@Override
public Validator mvcValidator() {
if (!ClassUtils.isPresent("javax.validation.Validator",
getClass().getClassLoader())) {
return super.mvcValidator();
}
return WebMvcValidator.get(getApplicationContext(), getValidator());
}
@Override
protected RequestMappingHandlerMapping createRequestMappingHandlerMapping() {
if (this.mvcRegistrations != null
&& this.mvcRegistrations.getRequestMappingHandlerMapping() != null) {
return this.mvcRegistrations.getRequestMappingHandlerMapping();
}
return super.createRequestMappingHandlerMapping();
}
@Override
protected ConfigurableWebBindingInitializer getConfigurableWebBindingInitializer() {
try {
return this.beanFactory.getBean(ConfigurableWebBindingInitializer.class);
}
catch (NoSuchBeanDefinitionException ex) {
return super.getConfigurableWebBindingInitializer();
}
}
@Override
protected ExceptionHandlerExceptionResolver createExceptionHandlerExceptionResolver() {
if (this.mvcRegistrations != null && this.mvcRegistrations
.getExceptionHandlerExceptionResolver() != null) {
return this.mvcRegistrations.getExceptionHandlerExceptionResolver();
}
return super.createExceptionHandlerExceptionResolver();
}
@Override
protected void configureHandlerExceptionResolvers(
List<HandlerExceptionResolver> exceptionResolvers) {
super.configureHandlerExceptionResolvers(exceptionResolvers);
if (exceptionResolvers.isEmpty()) {
addDefaultHandlerExceptionResolvers(exceptionResolvers);
}
if (this.mvcProperties.isLogResolvedException()) {
for (HandlerExceptionResolver resolver : exceptionResolvers) {
if (resolver instanceof AbstractHandlerExceptionResolver) {
((AbstractHandlerExceptionResolver) resolver)
.setWarnLogCategory(resolver.getClass().getName());
}
}
}
}
// 创建ContentNegotiationManager
@Bean
@Override
public ContentNegotiationManager mvcContentNegotiationManager() {
ContentNegotiationManager manager = super.mvcContentNegotiationManager();
List<ContentNegotiationStrategy> strategies = manager.getStrategies();
ListIterator<ContentNegotiationStrategy> iterator = strategies.listIterator();
while (iterator.hasNext()) {
ContentNegotiationStrategy strategy = iterator.next();
if (strategy instanceof PathExtensionContentNegotiationStrategy) {
iterator.set(new OptionalPathExtensionContentNegotiationStrategy(
strategy));
}
}
return manager;
}
}
@Configuration
@ConditionalOnEnabledResourceChain
static class ResourceChainCustomizerConfiguration {
@Bean
public ResourceChainResourceHandlerRegistrationCustomizer resourceHandlerRegistrationCustomizer() {
return new ResourceChainResourceHandlerRegistrationCustomizer();
}
}
interface ResourceHandlerRegistrationCustomizer {
void customize(ResourceHandlerRegistration registration);
}
private static class ResourceChainResourceHandlerRegistrationCustomizer
implements ResourceHandlerRegistrationCustomizer {
@Autowired
private ResourceProperties resourceProperties = new ResourceProperties();
@Override
public void customize(ResourceHandlerRegistration registration) {
ResourceProperties.Chain properties = this.resourceProperties.getChain();
configureResourceChain(properties,
registration.resourceChain(properties.isCache()));
}
private void configureResourceChain(ResourceProperties.Chain properties,
ResourceChainRegistration chain) {
Strategy strategy = properties.getStrategy();
if (strategy.getFixed().isEnabled() || strategy.getContent().isEnabled()) {
chain.addResolver(getVersionResourceResolver(strategy));
}
if (properties.isGzipped()) {
chain.addResolver(new GzipResourceResolver());
}
if (properties.isHtmlApplicationCache()) {
chain.addTransformer(new AppCacheManifestTransformer());
}
}
private ResourceResolver getVersionResourceResolver(
ResourceProperties.Strategy properties) {
VersionResourceResolver resolver = new VersionResourceResolver();
if (properties.getFixed().isEnabled()) {
String version = properties.getFixed().getVersion();
String[] paths = properties.getFixed().getPaths();
resolver.addFixedVersionStrategy(version, paths);
}
if (properties.getContent().isEnabled()) {
String[] paths = properties.getContent().getPaths();
resolver.addContentVersionStrategy(paths);
}
return resolver;
}
}
static final class WelcomePageHandlerMapping extends AbstractUrlHandlerMapping {
private static final Log logger = LogFactory
.getLog(WelcomePageHandlerMapping.class);
private WelcomePageHandlerMapping(Resource welcomePage,
String staticPathPattern) {
if (welcomePage != null && "/**".equals(staticPathPattern)) {
logger.info("Adding welcome page: " + welcomePage);
ParameterizableViewController controller = new ParameterizableViewController();
// WelcomePageHandlerMapping直接转发index.html
controller.setViewName("forward:index.html");
setRootHandler(controller);
setOrder(0);
}
}
@Override
public Object getHandlerInternal(HttpServletRequest request) throws Exception {
for (MediaType mediaType : getAcceptedMediaTypes(request)) {
if (mediaType.includes(MediaType.TEXT_HTML)) {
return super.getHandlerInternal(request);
}
}
return null;
}
private List<MediaType> getAcceptedMediaTypes(HttpServletRequest request) {
String acceptHeader = request.getHeader(HttpHeaders.ACCEPT);
return MediaType.parseMediaTypes(
StringUtils.hasText(acceptHeader) ? acceptHeader : "*/*");
}
}
/**
* Decorator to make {@link PathExtensionContentNegotiationStrategy} optional
* depending on a request attribute.
*/
static class OptionalPathExtensionContentNegotiationStrategy
implements ContentNegotiationStrategy {
private static final String SKIP_ATTRIBUTE = PathExtensionContentNegotiationStrategy.class
.getName() + ".SKIP";
private final ContentNegotiationStrategy delegate;
OptionalPathExtensionContentNegotiationStrategy(
ContentNegotiationStrategy delegate) {
this.delegate = delegate;
}
@Override
public List<MediaType> resolveMediaTypes(NativeWebRequest webRequest)
throws HttpMediaTypeNotAcceptableException {
Object skip = webRequest.getAttribute(SKIP_ATTRIBUTE,
RequestAttributes.SCOPE_REQUEST);
if (skip != null && Boolean.parseBoolean(skip.toString())) {
return Collections.emptyList();
}
return this.delegate.resolveMediaTypes(webRequest);
}
}
}
说在最后
本次仅代表个人观点，仅供参考。