在Spring MVC中使用工具类调用Service层时，Service类为null如何解决

因为平时在调用service层时都是在controller中，有配置扫描注入，spring会根据配置自动注入所依赖的服务层。但因我们写的工具类不属于controller层，所以当所写接口需要调用服务层是，常常会为NULL。下面就分享一个实践后可行的办法,如下图所示：@Componentpublic class SocketEquipment extends SubEquipment{private static IHomeDeviceTypeService devictTypeService;private static IHomeDeviceService deviceService;private static IHomeDataVersionService homeDataVersionService;private static IHomeSubDevicePropertiesService homeSubDevicePropertiesService;@Autowiredpublic void setUserInfo(IHomeDeviceTypeService devictTypeService,IHomeDeviceService deviceService,IHomeDataVersionService homeDataVersionService,IHomeSubDevicePropertiesService homeSubDevicePropertiesService){this.devictTypeService = devictTypeService;this.deviceService = deviceService;this.homeDataVersionService = homeDataVersionService;this.homeSubDevicePropertiesService = homeSubDevicePropertiesService;}}主要是：1.将此工具类加上@Component注解2.将所需调用的服务类设置成静态属性，并通过方法直接将服务层设置成工具类自己的属性即可。（虽然还没搞懂原理，但确实可行）------------------------------------------------------------------------------------------------近期在做串口或者comet4j时，发现也会使用到service层，但貌似上面方法未能有效。今日特地前来加补一种方法。因为我们使用的spring框架，所以所有的类基本都由spring容器同一加载管理。于是，我们可以自己再加载一下spring的xml配置文件，来获取我们所想要得到的对象，如下图：[java] view plain copypublic static ApplicationContext applicationContext = new ClassPathXmlApplicationContext("/spring-*.xml");  private static SystemalarmService systemalarmService = (SystemalarmService)applicationContext.getBean(SystemalarmService.class);  private static AlarmInfoService alarmInfoService = (AlarmInfoService)applicationContext.getBean(AlarmInfoService.class);