springMVC源码分析--AbstractDetectingUrlHandlerMapping（五）

上一篇博客springMVC源码分析--AbstractUrlHandlerMapping（三）中我们介绍了AbstractUrlHandlerMapping，主要介绍了一个handlerMap的url和Handler的关系存取的过程。

在上一博客中我们介绍了handlerMap有一个注册url和Handler关系的注册函数，这个函数的调用是在实现类AbstractDetectingUrlHandlerMapping中实现的，目的是springMVC容器启动时将url和handler的对应关系注册到handlerMap中。

AbstractDetectingUrlHandlerMapping 抽象类：通过重写initApplicationContext来注册Handler，调用detectHandlers方法会根据配置的detectHand-lersInAcestorContexts参数从springMVC容器或者springMVC集群父容器中找到所有bean的beanName，然后调用determineUrlsForHandler方法对每个

beanName解析出对应的urls，如果解析的结果不为空，则将解析出的urls和beanName注册到父类的map中。

//初始化容器@Overridepublic void initApplicationContext() throws ApplicationContextException {super.initApplicationContext();detectHandlers();}

在调用父类的super.initApplicationContext后就是注册每个bean和url的关系，调用detectHandlers

//注册每个bean对应的url的关系protected void detectHandlers() throws BeansException {if (logger.isDebugEnabled()) {logger.debug("Looking for URL mappings in application context: " + getApplicationContext());}//获取容器的所有bean的名字String[] beanNames = (this.detectHandlersInAncestorContexts ?BeanFactoryUtils.beanNamesForTypeIncludingAncestors(getApplicationContext(), Object.class) :getApplicationContext().getBeanNamesForType(Object.class));// Take any bean name that we can determine URLs for.//对每个beanName解析url，如果能解析到就注册到父类的map中for (String beanName : beanNames) {//子类具体去实现String[] urls = determineUrlsForHandler(beanName);if (!ObjectUtils.isEmpty(urls)) {// URL paths found: Let's consider it a handler.//将解析的url注册到父类registerHandler(urls, beanName);}else {if (logger.isDebugEnabled()) {logger.debug("Rejected bean name '" + beanName + "': no URL paths identified");}}}}

其中determineUrlsForHandler函数是在其子类中实现的，registerHandler函数操作是在父类AbstractUrlHandlerMapping中实现的，将bean和url的关系注册到handlerMap中。

AbstractDetectingUrlHandlerMapping的完整源码如下：

public abstract class AbstractDetectingUrlHandlerMapping extends AbstractUrlHandlerMapping {private boolean detectHandlersInAncestorContexts = false;public void setDetectHandlersInAncestorContexts(boolean detectHandlersInAncestorContexts) {this.detectHandlersInAncestorContexts = detectHandlersInAncestorContexts;}//初始化容器@Overridepublic void initApplicationContext() throws ApplicationContextException {super.initApplicationContext();detectHandlers();}//注册每个bean对应的url的关系protected void detectHandlers() throws BeansException {if (logger.isDebugEnabled()) {logger.debug("Looking for URL mappings in application context: " + getApplicationContext());}//获取容器的所有bean的名字String[] beanNames = (this.detectHandlersInAncestorContexts ?BeanFactoryUtils.beanNamesForTypeIncludingAncestors(getApplicationContext(), Object.class) :getApplicationContext().getBeanNamesForType(Object.class));// Take any bean name that we can determine URLs for.//对每个beanName解析url，如果能解析到就注册到父类的map中for (String beanName : beanNames) {//子类具体去实现String[] urls = determineUrlsForHandler(beanName);if (!ObjectUtils.isEmpty(urls)) {// URL paths found: Let's consider it a handler.//将解析的url注册到父类registerHandler(urls, beanName);}else {if (logger.isDebugEnabled()) {logger.debug("Rejected bean name '" + beanName + "': no URL paths identified");}}}}//抽象方法，子类中实现protected abstract String[] determineUrlsForHandler(String beanName);}