public class UserServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");UserService userService = (UserService) applicationContext.getBean("userService");userService.sayHello();}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}
}

<listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<context-param><param-name>contextConfigLocation</param-name><param-value>classpath:applicationContext.xml</param-value>
</context-param>

public class UserServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {/*也可用这种方式获得applicationContext:WebApplicationContext applicationContext = (WebApplicationContext) getServletContext().getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE);*/WebApplicationContext applicationContext = WebApplicationContextUtils.getWebApplicationContext(getServletContext());UserService userService = (UserService) applicationContext.getBean("userService");userService.sayHello();}public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}
}