spring容器WebApplicationContextUtils

1：在web.xml中定义listener
  <listener>
  <listener-class>com.BeanListener</listener-class>
  </listener>
2:在BeanListener.java中定义

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

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



public class BeanListener implements ServletContextListener {
private static WebApplicationContext context;

public void contextDestroyed(ServletContextEvent servletContextEvent) {


}


public void contextInitialized(ServletContextEvent servletContextEvent) {

context = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContextEvent.getServletContext());
}

public static Object getBean(String beanName) {
return context.getBean(beanName);
}
}