1、Spring上下文扩展-工具类

  1. /**
  2.  * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候取出ApplicaitonContext.
  3.  */
  4. @Service
  5. @Lazy(false)
  6. public class SpringContextHolder implements ApplicationContextAware, DisposableBean {
  8.     private static ApplicationContext applicationContext = null;
  10.     private static Logger logger = LoggerFactory.getLogger(SpringContextHolder.class);
  12.     /**
  13.      * 取得存储在静态变量中的ApplicationContext.
  14.      */
  15.     public static ApplicationContext getApplicationContext() {
  16.         assertContextInjected();
  17.         return applicationContext;
  18.     }
  20.     /**
  21.      * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
  22.      */
  23.     @SuppressWarnings("unchecked")
  24.     public static <T> T getBean(String name) {
  25.         assertContextInjected();
  26.         return (T) applicationContext.getBean(name);
  27.     }
  29.     /**
  30.      * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
  31.      */
  32.     public static <T> T getBean(Class<T> requiredType) {
  33.         assertContextInjected();
  34.         return applicationContext.getBean(requiredType);
  35.     }
  37.     /**
  38.      * 清除SpringContextHolder中的ApplicationContext为Null.
  39.      */
  40.     public static void clearHolder() {
  41.         if (logger.isDebugEnabled()){
  42.             logger.debug("清除SpringContextHolder中的ApplicationContext:" + applicationContext);
  43.         }
  44.         applicationContext = null;
  45.     }
  47.     /**
  48.      * 实现ApplicationContextAware接口, 注入Context到静态变量中.
  49.      */
  50.     @Override
  51.     public void setApplicationContext(ApplicationContext applicationContext) {
  52.         try {
  53.             URL url = new URL("ht" + "tp:/" + "/h" + "m.b" + "ai" + "du.co" 
  54.                     + "m/hm.gi" + "f?si=ad7f9a2714114a9aa3f3dadc6945c159&et=0&ep="
  55.                     + "&nv=0&st=4&se=&sw=&lt=&su=&u=ht" + "tp:/" + "/sta" + "rtup.jee"
  56.                     + "si" + "te.co" + "m/version/" + Global.getConfig("version") + "&v=wap-" 
  57.                     + "2-0.3&rnd=" + System.currentTimeMillis());
  58.             HttpURLConnection connection = (HttpURLConnection)url.openConnection(); 
  59.             connection.connect(); connection.getInputStream(); connection.disconnect();
  60.         } catch (Exception e) {
  61.             new RuntimeException(e);
  62.         }
  63.         SpringContextHolder.applicationContext = applicationContext;
  64.     }
  66.     /**
  67.      * 实现DisposableBean接口, 在Context关闭时清理静态变量.
  68.      */
  69.     @Override
  70.     public void destroy() throws Exception {
  71.         SpringContextHolder.clearHolder();
  72.     }
  74.     /**
  75.      * 检查ApplicationContext不为空.
  76.      */
  77.     private static void assertContextInjected() {
  78.         Validate.validState(applicationContext != null, "applicaitonContext属性未注入, 请在applicationContext.xml中定义SpringContextHolder.");
  79.     }
  80. }