详解spring cloud使用Hystrix实现单个方法的fallback

<dependency> 
      <groupid>org.springframework.cloud</groupid> 
      <artifactid>spring-cloud-starter-hystrix</artifactid> 
    </dependency> 

package com.chhliu.springboot.restful.controller;  
import org.springframework.beans.factory.annotation.autowired; 
import org.springframework.web.bind.annotation.getmapping; 
import org.springframework.web.bind.annotation.pathvariable; 
import org.springframework.web.bind.annotation.restcontroller;  
import com.chhliu.springboot.restful.feignclient.userfeignclient; 
import com.chhliu.springboot.restful.vo.user; 
import com.netflix.hystrix.contrib.javanica.annotation.hystrixcommand;  
@restcontroller 
public class resttemplatecontrollerhystrixcommand { 
   
  @autowired 
  private userfeignclient client; // 使用feign来消费restful服务 
   
  @getmapping("/get/{id}") 
  @hystrixcommand(fallbackmethod="findbyidfallback")// 使用hystrixcommand注解，在fallbackmethod属性中指定fallback的方法 
  public user findbyid(@pathvariable long id) { 
    return client.findbyid(id); 
  } 
   
    // 覆写fallbackmethod中指定的方法，注意，此方法的返回值，参数必须与原方法一致 
  public user findbyidfallback(long id){ 
    user u = new user(); 
    u.setname("zhangsan"); 
    u.setusername("chhliu"); 
    u.setid(9l); 
    return u; 
  } 
} 

@enablecircuitbreaker 

server.port:7904 
# spring boot服务注册到eureka server上的应用名称 
spring.application.name=springboot-rest-template-feign-hystrix 
eureka.instance.prefer-ip-address=true 
# eureka server注册服务的地址 
eureka.client.service-url.defaultzone=http://chhliu:chhliu123456@localhost:8764/eureka 
springboot-h2.ribbon.nfloadbalancerruleclassname=com.netflix.loadbalancer.retryrule 
hystrix.command.default.execution.isolation.thread.timeoutinmilliseconds: 1 #为了测试hystrix的fallback效果，此处将超时时间设置成1毫秒