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  • springboot获取IOC(ApplicationContext)实例

    在正常情况下 spring管理的类可直接调用Ioc容器中的实例,但在一些特殊情况下(例如拦截器中获取dao实例),Bean需要实现某个功能,但该功能必须借助于Spring容器才能实现,此时就必须让该Bean先获取Spring容器,

    spring提供了ApplicationContextAware接口,容器会自动检索实现该接口的类进行spring上下文注入

    import org.springframework.beans.BeansException;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.ApplicationContextAware;
    import org.springframework.stereotype.Component;
    
    import lombok.extern.slf4j.Slf4j;
    
    @Slf4j
    @Component
    public class SpringUtil implements ApplicationContextAware {
    
        private static ApplicationContext applicationContext;
    
        @Override
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
            if (SpringUtil.applicationContext == null) {
                SpringUtil.applicationContext = applicationContext;
            }
            log.info("ApplicationContext config success");
        }
    
        // 获取applicationContext
        public static ApplicationContext getApplicationContext() {
            return applicationContext;
        }
    
        // 通过name获取 Bean.
        public static Object getBean(String name) {
            return getApplicationContext().getBean(name);
        }
    
        // 通过class获取Bean.
        public static <T> T getBean(Class<T> clazz) {
            return getApplicationContext().getBean(clazz);
        }
    
        // 通过name,以及Clazz返回指定的Bean
        public static <T> T getBean(String name, Class<T> clazz) {
            return getApplicationContext().getBean(name, clazz);
        }
    
    }

    使用例子,拦截器中获取 redis缓存实例

    public class AccessInterceptor implements HandlerInterceptor {
    
        private IStringCacheService cache = SpringUtil.getBean(IStringCacheService.class);
    
        ......
        ......
        ......
        ......
        ......  
    }
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  • 原文地址:https://www.cnblogs.com/zincredible/p/10237672.html
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