2010-11-24

通过ApplicationContextAware获取bean
博客分类： Spring
 
BeanSpring.


加载Spring配置文件时，如果Spring配置文件中所定义的Bean类实现了ApplicationContextAware 接口，那么在加载Spring配置文件时，会自动调用ApplicationContextAware 接口中的 

public void setApplicationContext(ApplicationContext context) throws BeansException
 
方法，获得ApplicationContext 对象。 

前提必须在Spring配置文件中指定该类。 

 
 


Java代码  
1.public class SpringContextHolder implements ApplicationContextAware {  
2.  
3.     /** 
4.      * 以静态变量保存ApplicationContext,可在任意代码中取出ApplicaitonContext. 
5.      */  
6.    private static ApplicationContext context;  
7.  
8.    /** 
9.     * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量. 
10.     */  
11.    public void setApplicationContext(ApplicationContext context) {  
12.        SpringContextHolder.context =context;  
13.    }     
14.    public static ApplicationContext getApplicationContext() {  
15.        return context;  
16.    }  
17.    /** 
18.     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型. 
19.     */  
20.    public static <T> T getBean(String name) {  
21.        return (T) context.getBean(name);  
22.    }  
23.}  
 
 bean中：
 


Java代码  
1.<bean id="springContextHolder" class="com.enation.framework.context.spring.SpringContextHolder" />  
 
 
 
调用：
 


Java代码  
1.ICartManager cartManager = SpringContextHolder.getBean("cartManager");  
 
 
 
正常情况： 

 
 


Java代码  
1.public class AppManager extends ContextLoaderListener implements  ServletContextListener {  
2.  
3.    private ServletContext context;  
4.    private WebApplicationContext webApplicationContext;  
5.  
6.    public void contextInitialized(ServletContextEvent sce) {  
7.        this.context = sce.getServletContext();  
8.        this.webApplicationContext = WebApplicationContextUtils.getRequiredWebApplicationContext(context);  
9.        this.context.setAttribute("WEBAPPLICATIONCONTEXT", webApplicationContext);  
10.  
11.    ｝  
   


Java代码  
1.HttpSession session = request.getSession();  
2.WebApplicationContext webApplicationContext = (WebApplicationContext)session.getServletContext().getAttribute("WEBAPPLICATIONCONTEXT");  
3.UnsubscribeEmailFacade unsubscribeEmailFacade = (UnsubscribeEmailFacade)webApplicationContext.getBean("unsubscribeEmailFacade");