springmvc源碼分析三

spring ioc爲我們提供了自定義擴展xml,在spring使用篇中我對本章做了詳細的介紹。接下來我們開始分析springmvc組件

org.springframework.web.servlet.config.MvcNamespaceHandler

public class MvcNamespaceHandler extends NamespaceHandlerSupport {

	@Override
	public void init() {
		registerBeanDefinitionParser("annotation-driven", new AnnotationDrivenBeanDefinitionParser());
		registerBeanDefinitionParser("default-servlet-handler", new DefaultServletHandlerBeanDefinitionParser());
		registerBeanDefinitionParser("interceptors", new InterceptorsBeanDefinitionParser());
		registerBeanDefinitionParser("resources", new ResourcesBeanDefinitionParser());
		registerBeanDefinitionParser("view-controller", new ViewControllerBeanDefinitionParser());
		registerBeanDefinitionParser("redirect-view-controller", new ViewControllerBeanDefinitionParser());
		registerBeanDefinitionParser("status-controller", new ViewControllerBeanDefinitionParser());
		registerBeanDefinitionParser("view-resolvers", new ViewResolversBeanDefinitionParser());
		registerBeanDefinitionParser("tiles-configurer", new TilesConfigurerBeanDefinitionParser());
		registerBeanDefinitionParser("freemarker-configurer", new FreeMarkerConfigurerBeanDefinitionParser());
		registerBeanDefinitionParser("groovy-configurer", new GroovyMarkupConfigurerBeanDefinitionParser());
		registerBeanDefinitionParser("script-template-configurer", new ScriptTemplateConfigurerBeanDefinitionParser());
		registerBeanDefinitionParser("cors", new CorsBeanDefinitionParser());
	}

}

org.springframework.web.servlet.config.DefaultServletHandlerBeanDefinitionParser#parse

@Override
	@Nullable
	public BeanDefinition parse(Element element, ParserContext parserContext) {
		//
		Object source = parserContext.extractSource(element);
        // 獲取屬性值
		String defaultServletName = element.getAttribute("default-servlet-name");
		// 創建root對象
		RootBeanDefinition defaultServletHandlerDef = new RootBeanDefinition(DefaultServletHttpRequestHandler.class);
		
		defaultServletHandlerDef.setSource(source);
		defaultServletHandlerDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
		if (StringUtils.hasText(defaultServletName)) {
			defaultServletHandlerDef.getPropertyValues().add("defaultServletName", defaultServletName);
		}
		String defaultServletHandlerName = parserContext.getReaderContext().generateBeanName(defaultServletHandlerDef);
		// 註冊
		parserContext.getRegistry().registerBeanDefinition(defaultServletHandlerName, defaultServletHandlerDef);
		// 
		parserContext.registerComponent(new BeanComponentDefinition(defaultServletHandlerDef, defaultServletHandlerName));

		Map<String, String> urlMap = new ManagedMap<>();
		urlMap.put("/**", defaultServletHandlerName);

		RootBeanDefinition handlerMappingDef = new RootBeanDefinition(SimpleUrlHandlerMapping.class);
		handlerMappingDef.setSource(source);
		handlerMappingDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
		handlerMappingDef.getPropertyValues().add("urlMap", urlMap);

		String handlerMappingBeanName = parserContext.getReaderContext().generateBeanName(handlerMappingDef);
		// 註冊handler
		parserContext.getRegistry().registerBeanDefinition(handlerMappingBeanName, handlerMappingDef);
		parserContext.registerComponent(new BeanComponentDefinition(handlerMappingDef, handlerMappingBeanName));

		// Ensure BeanNameUrlHandlerMapping (SPR-8289) and default HandlerAdapters are not "turned off"
		MvcNamespaceUtils.registerDefaultComponents(parserContext, source);

		return null;
	}