Spring NamespaceHandlerResolver xml的标签加载的扩展 和 ApplicationContext

Posted 2021-03-24 java.matt

NamespaceHandlerResolver

public NamespaceHandler resolver(String namespaceUri);

 

DefaultNamespaceHandlerResolver返回执行标签解析的 NamespaceHandler对象

DefaultNamespaceHandlerResolver implements NamespaceHandlerResolver 

default_handler_mappings_location = "META-INF/spring.handlers";

 

spring.handlers文件的配置使用的NamespaceHandler对象

http://www.springframework.org/schema/aop=cn.tk.***.aop.config.AopNamespaceHandler

 

AopNamespaceHandler extends NamespaceHandlerSupport

执行注册 BeanDefinitionParser 对象

public void init(){

    registrerBeanDefinitionParser("config", new ConfigBeanDefinitionParser());

}

AOP标签的解析交给ConfigBeanDefinitionParser对象解析

 

 

ApplicationContext

 

ClassPathXmlApplicationContext --> AbstractXmlApplicationContext --> AbstratcRefreshableConfigApplicationContext --> 

AbstractRefreshableApplicationContext --> AbstractApplicationContext

 

AbstractApplicationContext 中 refresh()方法

public void refresh() {

prepareRefresh();

获取BeanFactory  

AutowireCapableBeanFactory beanFactory = obtainFreshBeanFactory();

执行 BeanFactoryPostProcessor 和 BeanDefinitionRegistryPostProcessor

registerBeanPostProcessors(beanFactory);

执行Bean的getBean()方法

finishBeanFactoryInitialization(beanFactory);

}