获取Spring下上文

获取Spring上下文
Servlet中：

ApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(ServletActionContext.getServletContext());   //获取所有Spring中的所有bean   String [] names = ctx.getBeanDefinitionNames();   for(int i=0;i<names.length;i++){       System.out.println("上下文实例："+names[i]);   }   //根据名称获取单个bean   LoginAction action=(LoginAction)ctx.getBean("action");  

ApplicationContext ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(request.getSession().getServletContext());