Servlet Contect Listenerを利用してspringコンテキストを取得します.

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

public class SpringContextListener implements ServletContextListener {
	private ApplicationContext applicationContext;

	public void contextDestroyed(ServletContextEvent arg0) {
		// TODO Auto-generated method stub
		
	}

	public void contextInitialized(ServletContextEvent event) {
		applicationContext = WebApplicationContextUtils.getWebApplicationContext(event.getServletContext()); //  spring   	
		//applicationContext.getBean("userDao");
	}
}

 
web.xml
 

<listener>
    <listener-class>com.SpringContextListener</listener-class>
  </listener>