自定义SpringContextHolder获取bean实例(一)

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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。

    public class SpringContextHolder implements ApplicationContextAware {                 /**           * 以静态变量保存ApplicationContext,可在任意代码中取出ApplicaitonContext.           */          private static ApplicationContext context;                /**          * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.          */          public void setApplicationContext(ApplicationContext context) {              SpringContextHolder.context =context;          }             public static ApplicationContext getApplicationContext() {              return context;          }          /**          * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.          */          public static <T> T getBean(String name) {              return (T) context.getBean(name);          }      }

bean中：

Java代码

<bean id="springContextHolder" class="com.enation.framework.context.spring.SpringContextHolder" />

调用：

Java代码

ICartManager cartManager = SpringContextHolder.getBean("cartManager");

正常情况：

Java代码

    public class AppManager extends ContextLoaderListener implements  ServletContextListener {                private ServletContext context;          private WebApplicationContext webApplicationContext;                public void contextInitialized(ServletContextEvent sce) {              this.context = sce.getServletContext();              this.webApplicationContext = WebApplicationContextUtils.getRequiredWebApplicationContext(context);              this.context.setAttribute("WEBAPPLICATIONCONTEXT", webApplicationContext);                ｝

Java代码

HttpSession session = request.getSession();  WebApplicationContext webApplicationContext = (WebApplicationContext)session.getServletContext().getAttribute("WEBAPPLICATIONCONTEXT");  UnsubscribeEmailFacade unsubscribeEmailFacade = (UnsubscribeEmailFacade)webApplicationContext.getBean("unsubscribeEmailFacade");

法2：

org.springframework.web.context.ContextLoader

// 获取spring bean容器      WebApplicationContext wac = ContextLoader.getCurrentWebApplicationContext();      ISysConfigDao sysconfigdao = (ISysConfigDao) wac.getBean("iSysConfigDao");

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