springcloud hystrix 实现服务降级解决服务器雪崩

导入依赖

<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-feign</artifactId>
		</dependency>
		 
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-hystrix</artifactId>
		</dependency><dependency>
			<groupId>org.springfr