springmvc源码学习2

public abstract class AbstractHandlerMethodMapping<T> extends AbstractHandlerMapping implements InitializingBean

//实现了InitializingBean接口
public void afterPropertiesSet() {
		initHandlerMethods();
	}

	/**
	 * Scan beans in the ApplicationContext, detect and register handler methods.
	 * @see #isHandler(Class)
	 * @see #getMappingForMethod(Method, Class)
	 * @see #handlerMethodsInitialized(Map)
	 */
	protected void initHandlerMethods() {
		if (logger.isDebugEnabled()) {
			logger.debug("Looking for request mappings in application context: " + getApplicationContext());
		}

		String[] beanNames = (this.detectHandlerMethodsInAncestorContexts ?
				BeanFactoryUtils.beanNamesForTypeIncludingAncestors(getApplicationContext(), Object.class) :
				getApplicationContext().getBeanNamesForType(Object.class));

		for (String beanName : beanNames) {
			if (isHandler(getApplicationContext().getType(beanName))){
   //如果是有@Controller @RequestMapping注解的
				detectHandlerMethods(beanName);
			}
		}
		handlerMethodsInitialized(getHandlerMethods());
	}

protected void detectHandlerMethods(final Object handler) {
		Class<?> handlerType = (handler instanceof String) ?
				getApplicationContext().getType((String) handler) : handler.getClass();

		final Class<?> userType = ClassUtils.getUserClass(handlerType);

		Set<Method> methods = HandlerMethodSelector.selectMethods(userType, new MethodFilter() {
			public boolean matches(Method method) {
				return getMappingForMethod(method, userType) != null;
			}
		});

		for (Method method : methods) {
			T mapping = getMappingForMethod(method, userType);
			registerHandlerMethod(handler, method, mapping);
		}
	}

protected void registerHandlerMethod(Object handler, Method method, T mapping) {
		HandlerMethod newHandlerMethod = createHandlerMethod(handler, method);
		HandlerMethod oldHandlerMethod = handlerMethods.get(mapping);
		if (oldHandlerMethod != null && !oldHandlerMethod.equals(newHandlerMethod)) {
			throw new IllegalStateException("Ambiguous mapping found. Cannot map '" + newHandlerMethod.getBean()
					+ "' bean method \n" + newHandlerMethod + "\nto " + mapping + ": There is already '"
					+ oldHandlerMethod.getBean() + "' bean method\n" + oldHandlerMethod + " mapped.");
		}

		this.handlerMethods.put(mapping, newHandlerMethod);
		if (logger.isInfoEnabled()) {
			logger.info("Mapped \"" + mapping + "\" onto " + newHandlerMethod);
		}

		Set<String> patterns = getMappingPathPatterns(mapping);
		for (String pattern : patterns) {
			if (!getPathMatcher().isPattern(pattern)) {
				this.urlMap.add(pattern, mapping);
			}
		}
	}

 注册后 ,然后将带有@Controller @RequestMapping注解的,url和对应的类方法封装成HandlerMethod对象,缓存在handlerMethods  map中

private final Map<T, HandlerMethod> handlerMethods = new LinkedHashMap<T, HandlerMethod>();

拦截器在initApplicationContext方法中定义了(前面讲过,通过aware接口 调用这个initApplicationContext方法),会查找bean容器,把拦截器封装成MappedInterceptor对象。缓存在

mappedInterceptors中

private final List<MappedInterceptor> mappedInterceptors = new ArrayList<MappedInterceptor>();

之后 ,当有请求来时,在handlerMethods中找到请求url对应的handlerMethod,和mappedInterceptors中查找拦截器,组成一个HandlerExecutionChain对象。

 

猜你喜欢

转载自cainiaoboke.iteye.com/blog/2333668