【SpringCloud】（十四）：Feign对Hystrix的支持 fallbackFactory

  前面的文章中提到了fallback，这里我们描述一个它的增强版。fallbackFactory。都是实现断路器的功能。

UserFeignClient

package com.dynamic.cloud.feign;import org.springframework.cloud.netflix.feign.FeignClient;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import com.dynamic.cloud.entity.User;//@FeignClient(name="microservice-provider-user",fallback =HystrixClientFallback.class,fallbackFactory=HystrixClientFallbackFactory.class)@FeignClient(name="microservice-provider-user",fallbackFactory=HystrixClientFallbackFactory.class)public interface UserFeignClient {@RequestMapping(value="/simple/{id}",method = RequestMethod.GET) //只能是RequestMappingpublic User findById(@PathVariable("id") Long id); //@PathVariable需要设置括号中的名称}

加上fallbackFactory

对应的类是HystrixClientFallbackFactory 

package com.dynamic.cloud.feign;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.stereotype.Component;import com.dynamic.cloud.entity.User;import feign.hystrix.FallbackFactory;@Componentpublic class HystrixClientFallbackFactory implements FallbackFactory<UserFeignClient> {private static final Logger logger = LoggerFactory.getLogger(HystrixClientFallbackFactory.class);@Overridepublic UserFeignClient create(Throwable cause) {HystrixClientFallbackFactory.logger.info("fallback reason was: {} " ,cause.getMessage());return new UserFeignClientWithFactory(){@Overridepublic User findById(Long id) {User user = new User();user.setId(-1L);return user;}};}}

该类中存在UserFeignClientWithFactory，它继承了UserFeignClient。这里实现了它的方法。

package com.dynamic.cloud.feign;public interface UserFeignClientWithFactory extends UserFeignClient {}

  我们把用户微服务停掉之后，断路器打开，执行fallbackfactory 指定的类中方法。HystrixClientFallbackFactory 。