SpringCloud之Ribbon负载均衡

<!-- Ribbon相关 -->
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-eureka</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-ribbon</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-config</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

server:
  port: 80
eureka:
  client:
    register-with-eureka: false
    service-url: 
      defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/,http://eureka7003.com:7003/eureka/  

package com.atguigu.springcloud.cfgbeans;
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;
/**
 * 配置类
 * @ClassName:  ConfigBean   
 * @Description:TODO
 * @author: jp
 * @date:   2019年6月3日 下午4:42:09   
 *     
 * @Copyright: 2019 www.tydic.com Inc. All rights reserved. 
 *
 */
@Configuration
public class ConfigBean {
  @Bean
  @LoadBalanced//Spring Cloud Ribbon是基于Netflix Ribbon实现的一套客户端       负载均衡的工具。
  public RestTemplate getRestTemplate() {
    return new RestTemplate();
  }
}

package com.atguigu.springcloud.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
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 com.atguigu.springcloud.entities.Dept;
/**
 * 消费方控制器
 * @ClassName:  DeptController_Consumer   
 * @Description:TODO
 * @author: jp
 * @date:   2019年6月3日 下午4:48:40   
 *     
 * @Copyright: 2019 www.tydic.com Inc. All rights reserved. 
 *
 */
@RestController
public class DeptController_Consumer {
  /**
   * 使用 使用restTemplate访问restful接口非常的简单粗暴无脑。 (url, requestMap,
   * ResponseBean.class)这三个参数分别代表 REST请求地址、请求参数、HTTP响应转换被转换成的对象类型。
   */
  @Autowired
  RestTemplate restTemplate;
  //private static final String REST_URL_PREFIX = "http://localhost:8001";  //之前是直接通过对目的的服务提供者获取
  private static final String REST_URL_PREFIX = "http://MICROSERVICECLOUD-DEPT";  //现在通过euraka获取服务
  @RequestMapping(value = "/consumer/dept/add")
  public boolean add(Dept dept)
  {
    return restTemplate.postForObject(REST_URL_PREFIX + "/dept/add", dept, Boolean.class);
  }
  @RequestMapping(value = "/consumer/dept/get/{id}")
  public Dept get(@PathVariable("id") Long id)
  {
    return restTemplate.getForObject(REST_URL_PREFIX + "/dept/get/" + id, Dept.class);
  }
  @SuppressWarnings("unchecked")
  @RequestMapping(value = "/consumer/dept/list")
  public List<Dept> list()
  {
    return restTemplate.getForObject(REST_URL_PREFIX + "/dept/list", List.class);
  }
  // 测试@EnableDiscoveryClient,消费端可以调用服务发现
  @RequestMapping(value = "/consumer/dept/discovery")
  public Object discovery()
  {
    return restTemplate.getForObject(REST_URL_PREFIX + "/dept/discovery", Object.class);
  }
}

package com.atguigu.springcloud;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@EnableEurekaClient
public class DeptConsumer80_App {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    SpringApplication.run(DeptConsumer80_App.class, args);
  }
}

package com.atguigu.springcloud.cfgbeans;
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;
import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RetryRule;
@Configuration
public class ConfigBean //boot -->spring   applicationContext.xml --- @Configuration配置   ConfigBean = applicationContext.xml
{ 
  @Bean
  @LoadBalanced//Spring Cloud Ribbon是基于Netflix Ribbon实现的一套客户端       负载均衡的工具。
  public RestTemplate getRestTemplate()
  {
    return new RestTemplate();
  }
   //配置负载均衡的策略为随机，默认算法为轮询算法
  @Bean
  public IRule myRule()
  {
    //这里可以修改算法
    //return new RoundRobinRule();
    return new RandomRule();//达到的目的，用我们重新选择的随机算法替代默认的轮询。
    //return new RetryRule();
  }
}