Spring 加载Controller逻辑的源码笔记

org.springframework.web.servlet.handler.AbstractHandlerMethodMapping#initHandlerMethods 进行加载Controller：

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 (!beanName.startsWith(SCOPED_TARGET_NAME_PREFIX)) {
				Class<?> beanType = null;
				try {
					beanType = getApplicationContext().getType(beanName);
				}
				catch (Throwable ex) {
					// An unresolvable bean type, probably from a lazy bean - let's ignore it.
					if (logger.isDebugEnabled()) {
						logger.debug("Could not resolve target class for bean with name '" + beanName + "'", ex);
					}
				}
				if (beanType != null && isHandler(beanType)) {  //isHandler 是重点方法，判断是否是Controller

detectHandlerMethods(beanName); } } } handlerMethodsInitialized(getHandlerMethods()); }

　org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#isHandler 源码如下：

	/**
	 * {@inheritDoc}
	 * Expects a handler to have a type-level @{@link Controller} annotation.
	 */
	@Override
	protected boolean isHandler(Class<?> beanType) {
		return (AnnotatedElementUtils.hasAnnotation(beanType, Controller.class) ||
				AnnotatedElementUtils.hasAnnotation(beanType, RequestMapping.class));
	}　　

　

isHandler 进行判断是否是有Controller或者RequestMapping注解，如果有的话就开始进行映射Controller的方法。
具体映射逻辑在org.springframework.web.servlet.handler.AbstractHandlerMethodMapping#detectHandlerMethods中。