使用web.xml方式加载Spring时，获取Spring context的两种方式：
1、servlet方式加载时：
【web.xml】
<servlet>
<servlet-name>dispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext</param-value>
</init-param>
</servlet>
【jsp/servlet】
ServletContext context = getServletContext();XmlWebApplicationContext applicationContext = (XmlWebApplicationContext) context.getAttribute("org.springframework.web.servlet.FrameworkServlet.CONTEXT.dispatcherServlet");DataSource dataSource=(DataSource)applicationContext.getBean("dataSource");
2、listener方式加载时：
【web.xml】
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
【jsp/servlet】
ServletContext context = getServletContext();WebApplicationContext applicationContext = WebApplicationContextUtils.getWebApplicationContext(context);DataSource dataSource=(DataSource)applicationContext.getBean("dataSource");
原文：http://chanson.iteye.com/blog/223263
