</pre>在spring mvc项目中,可以通过实现<pre code_snippet_id="1602194" snippet_file_name="blog_20160308_2_8772120" name="code" class="java">ApplicationContextAware
来获得ApplicationContext,
public class ContextHolder implements ApplicationContextAware {
private static ApplicationContext context;
}
实现接口中方法
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
context = applicationContext;
}
然后注入实现类:
<bean id="SpringContextHolder" class="com.*.ContextHolder"></bean>
原理:
类AbstractApplicationContext中的prepareBeanFactory这个方法中向beanFactory注册了一个beanPostProcessor。
beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this));
ApplicationContextAwareProcessor 在初始化前会执行this.invokeAwareInterfaces(bean);
private void invokeAwareInterfaces(Object bean) {
if(bean instanceof Aware) {
if(bean instanceof EnvironmentAware) {
((EnvironmentAware)bean).setEnvironment(this.applicationContext.getEnvironment());
}
if(bean instanceof EmbeddedValueResolverAware) {
((EmbeddedValueResolverAware)bean).setEmbeddedValueResolver(new ApplicationContextAwareProcessor.EmbeddedValueResolver(this.applicationContext.getBeanFactory()));
}
if(bean instanceof ResourceLoaderAware) {
((ResourceLoaderAware)bean).setResourceLoader(this.applicationContext);
}
if(bean instanceof ApplicationEventPublisherAware) {
((ApplicationEventPublisherAware)bean).setApplicationEventPublisher(this.applicationContext);
}
if(bean instanceof MessageSourceAware) {
((MessageSourceAware)bean).setMessageSource(this.applicationContext);
}
<span style="color:#ff0000;"> if(bean instanceof ApplicationContextAware) {
((ApplicationContextAware)bean).setApplicationContext(this.applicationContext);
}</span>
}
//调用ApplicationContextAware接口实现类的setApplicationContext方法。
}
对了 这个不能忘了 web.xml里
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>