Android判断Service是否运行

/** 
        * 用来判断服务是否运行. 
        * @param context 
        * @param className 判断的服务名字 
        * @return true 在运行 false 不在运行 
        */
       public static boolean isServiceRunning(Context mContext,String className) { 
           boolean isRunning = false; 
ActivityManager activityManager = (ActivityManager) 
mContext.getSystemService(Context.ACTIVITY_SERVICE);  
           List<ActivityManager.RunningServiceInfo> serviceList  
           = activityManager.getRunningServices(30); 
          if (!(serviceList.size()>0)) { 
               return false; 
           } 
           for (int i=0; i<serviceList.size(); i++) { 
               if (serviceList.get(i).service.getClassName().equals(className) == true) { 
                   isRunning = true; 
                   break; 
               } 
           } 
           return isRunning; 
       }