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

package com.stonegeek;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;/*** Created by StoneGeek on 2018/5/28.* 博客地址：http://www.cnblogs.com/sxkgeek*/
@EnableCircuitBreaker
@EnableDiscoveryClient
@SpringBootApplication
public class RibbonConsumerApplication {@Bean@LoadBalancedRestTemplate restTemplate(){return new RestTemplate();}public static void main(String[] args) {SpringApplication.run(RibbonConsumerApplication.class, args);}
}

package com.stonegeek.service;import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;import java.util.logging.Logger;/*** Created by StoneGeek on 2018/5/29.* 博客地址：http://www.cnblogs.com/sxkgeek*/
@Service
public class HelloService {private final Logger logger =Logger.getLogger(String.valueOf(getClass()));@AutowiredRestTemplate restTemplate;@HystrixCommand(fallbackMethod = "helloFallback")public String helloService(){//加logger更清晰的看出执行时间long start =System.currentTimeMillis();String result=restTemplate.getForEntity("http://SERVICE-HELLO/hello",String.class).getBody();long end=System.currentTimeMillis();logger.info("Spend time:"+(end-start));return result;}public String helloFallback(){return "error";}}

package com.stonegeek.controller;import com.stonegeek.service.HelloService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;/*** Created by StoneGeek on 2018/5/28.* 博客地址：http://www.cnblogs.com/sxkgeek*/
@RestController
public class ConsumerController {/*** @Author: StoneGeek* @Date: 2018/5/29* @Description:之前不加断路器代码*/
//    @Autowired
//    RestTemplate restTemplate;
//
//    @RequestMapping(value = "/ribbon-consumer",method = RequestMethod.GET)
//    public String helloConsumer(){
//        return restTemplate.getForEntity("http://SERVICE-HELLO/hello",String.class).getBody();
//    }/*** @Author: StoneGeek* @Date: 2018/5/29* @Description: 加了断路器代码*/@AutowiredHelloService helloService;@RequestMapping(value = "/ribbon-consumer",method = RequestMethod.GET)public String helloConsumer(){return helloService.helloService();}}

package com.stonegeek.controller;import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.logging.Logger;/*** Created by StoneGeek on 2018/5/27.* 博客地址：http://www.cnblogs.com/sxkgeek*/
@RestController
public class HelloController {private final Logger logger =Logger.getLogger(String.valueOf(getClass()));@Autowiredprivate DiscoveryClient client;/*** @Author: StoneGeek* @Date: 2018/5/29 * @Description:不加线服务塞的代码*/
//    @RequestMapping(value = "hello",method = RequestMethod.GET)
//    public String  index(){
//        ServiceInstance instance=client.getLocalServiceInstance();
//        logger.info("/hello, host:"+instance.getHost()+", service_id:"+instance.getServiceId()+"service_port:"+instance.getPort());
//        return "hello world ";
//    }/*** @Author: StoneGeek* @Date: 2018/5/29* @Description: 加了Thread.sleep(3000)的服务阻塞代码，由于Hystrix默认超时时间为2000毫秒，* 所以这里采用了0至3000的随机数以让处理过程有一定概率发生超时来触发断路器*/@RequestMapping(value = "/hello",method = RequestMethod.GET)public String  index() throws InterruptedException {ServiceInstance instance=client.getLocalServiceInstance();int sleepTime=new Random().nextInt(3000);logger.info("sleepTime:"+sleepTime);Thread.sleep(sleepTime);logger.info("sleepTime:"+sleepTime+"/hello, host:"+instance.getHost()+", service_id:"+instance.getServiceId()+"service_port:"+instance.getPort());return "hello world ";}
}