在enum中@Autowired注解无效

需求大概如下，在枚举对象LAYER_CARETAKER中调用@Autowried注解进行注入, 但是发现layerMapper结果为null。

private enum Caretaker{


    LAYER_CARETAKER(LAYER){
        @Autowired
        private LayerMapper layerMapper; 
        @Override
        public List<TreeNodeVO> childrenNodes(Long parentId) {
            List<Layer> floorList = floorMapper.selectList(new EntityWrapper<>());
            return floorList.stream()
                    .map(item-> new TreeNodeVO(item.getId(),item.getName(),getGrade()))
                    .collect(Collectors.toList());
        }
    };

       // 省略属性、方法    

}

 

然后我改为了：

@Service
@Slf4j
public class CourseArrangementServiceImpl implements CourseArrangementService, ApplicationContextAware {


    // 注意
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        Caretaker.setApplicationContext(applicationContext);
    }


    //---------------------------------

    @Slf4j
    private enum Caretaker implements TreeNodeCaretaker {

        /**
         *
         */
        LAYER_CARETAKER(LAYER){
            @Override
            public List<TreeNodeVO> childrenNodes(Long parentId) {
                LayerMapper floorMapper = getApplicationContext().getBean("layerMapper", LayerMapper.class);
                List<Layer> floorList = floorMapper.selectList(new EntityWrapper<>());
                return floorList.stream()
                        .map(item-> new TreeNodeVO(item.getId(),item.getName(),getGrade()))
                        .collect(Collectors.toList());
            }
        },
        ;

        private static ApplicationContext applicationContext;

        public ApplicationContext getApplicationContext() {
            return applicationContext;
        }

        public static void setApplicationContext(ApplicationContext applicationContext){
            Caretaker.applicationContext = applicationContext;
        }

        // 略
    }

}

 

如有问题，欢迎指出~