这个小demo只是自学的时候想简单练习一下   因此不包含mybatis，数据查询是写死的   只是大概测试一下eureka   

一、服务端

 1、导入依赖

<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>

2、springboot启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;@SpringBootApplication
// 启用EurekaServer
@EnableEurekaServer
public class EurekaApp {public static void main(String[] args) {SpringApplication.run(EurekaApp.class,args);}
}

3、配置文件

# eureka 配置
# eureka 一共有4部分 配置
# 1. dashboard:eureka的web控制台配置
# 2. server:eureka的服务端配置
# 3. client:eureka的客户端配置
# 4. instance:eureka的实例配置server:port: 8761  #默认8761端口eureka:instance:hostname: localhost # 主机名lease-renewal-interval-in-seconds: 30lease-expiration-duration-in-seconds: 90prefer-ip-address: true  #是否将ip注册到eureka中  默认falseip-address: 127.0.0.1client:service-url:defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka # eureka服务端地址，将来客户端使用该地址和eureka进行通信register-with-eureka: false # 是否将自己的路径 注册到eureka上。eureka server 不需要的，eureka provider client 需要fetch-registry: false # 是否需要从eureka中抓取路径。eureka server 不需要的，eureka consumer client 需要server:enable-self-preservation: false #关闭自我保护机制eviction-interval-timer-in-ms: 3000 #清理间隔

二、客户端

因为在springcloud中所有微服务模块都可能是生产者和消费者  因此  我这里简单的定义了两个小模块  一个是生产者、一个是消费者   在真实生产环境中   没有严格意义上的生产者与消费者的区别

提供者

1、导入依赖

<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

2、启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;@SpringBootApplication
@EnableEurekaClient
public class ProviderApp {public static void main(String[] args) {SpringApplication.run(ProviderApp.class,args);}
}

3、提供者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.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("/goods")
public class GoodsController {@Autowiredprivate GoodsService goodsService;@GetMapping("/findOne/{id}")public Goods findOne(@PathVariable("id") int id){Goods goods = goodsService.findOne(id);//        System.out.println("goods2 = " + goods);return goods;}
}

4、配置文件

server:port: 8000
eureka:instance:hostname: localhost # 主机名prefer-ip-address: trueip-address: 127.0.0.1instance-id: ${eureka.instance.ip-address}:${spring.application.name}:${server.port} # 设置web控制台显示的 实例idlease-renewal-interval-in-seconds: 3 # 每隔3 秒发一次心跳包lease-expiration-duration-in-seconds: 9 # 如果9秒没有发心跳包，服务器呀，你把我干掉吧~client:service-url:defaultZone: http://localhost:8761/eureka # eureka服务端地址，将来客户端使用该地址和eureka进行通信
#      defaultZone: http://eureka-server1:8761/eureka,http://eureka-server2:8762/eureka # eureka服务端地址，将来客户端使用该地址和eureka进行通信
spring:application:name: eureka-provider # 设置当前应用的名称。将来会在eureka中Application显示。将来需要使用该名称来获取路径

消费者

1、导入依赖

<dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

2、启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;@SpringBootApplication
@EnableEurekaClient
public class ConsumerApp {public static void main(String[] args) {SpringApplication.run(ConsumerApp.class,args);}
}

因为在服务调用的时候需要在Java代码中访问 restful 服务  我使用的时RestTemplate来完成远程调用

RestTemplate是Spring提供的用于访问Rest服务的客户端，RestTemplate提供了多种便捷访问远程Http服务的方法,能够大大提高客户端的编写效率。其功能与 HttpClient 类似，但是 RestTemplate 实现更优雅，使用更方便

3、RestTemplate 注入

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;@Configuration
public class RestTemplateConfig {@LoadBalanced//调用负载均衡@Beanpublic RestTemplate restTemplate(){return new RestTemplate();}
}

4、消费者controller

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.context.annotation.Import;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;import java.util.List;@RestController
@RequestMapping("/order")
public class OrderController {@Autowiredprivate RestTemplate restTemplate;@Autowiredprivate DiscoveryClient discoveryClient;@GetMapping("/goods/{id}")public Goods findGoodsById(@PathVariable("id") int id) {System.out.println("findGoodsById..." + id);List<ServiceInstance> instances = discoveryClient.getInstances("eureka-provider");if (instances == null || instances.size() == 0) {return null;}ServiceInstance serviceInstance = instances.get(0);String host = serviceInstance.getHost();System.out.println("host = " + host);int port = serviceInstance.getPort();
//        String url = "http://localhost:8000/goods/findOne/";String url = "http://"+host+":"+port+"/goods/findOne/";//远程调用Goods服务中的findOne接口Goods goods = restTemplate.getForObject( url+ id, Goods.class);return goods;}@GetMapping("/goods2/{id}")public Goods findGoodsById2(@PathVariable("id") int id) {System.out.println("findGoodsById..." + id);String url = "http://eureka-provider/goods/findOne/";Goods goods = restTemplate.getForObject( url + id, Goods.class);//远程调用Goods服务中的findOne接口return goods;}
}

5、配置文件

server:port: 9000
eureka:instance:hostname: localhost # 主机名prefer-ip-address: trueip-address: 127.0.0.1instance-id: ${eureka.instance.ip-address}:${spring.application.name}:${server.port} # 设置web控制台显示的 实例idlease-renewal-interval-in-seconds: 3 # 每隔3 秒发一次心跳包lease-expiration-duration-in-seconds: 9 # 如果9秒没有发心跳包，服务器呀，你把我干掉吧~client:service-url:defaultZone: http://localhost:8761/eureka # eureka服务端地址，将来客户端使用该地址和eureka进行通信registry-fetch-interval-seconds: 10 #获取服务地址列表间隔时间  默认30秒
spring:application:name: eureka-consumer # 设置当前应用的名称。将来会在eureka中Application显示。将来需要使用该名称来获取路径

仅仅留下一部分代码   导包也未全部粘贴进入   仅留予自己忘记时有个参考