项目地址：

github地址

添加自定义算法的步骤

1.主启动类添加注解: @RibbonClient(name="DEBUGGGCLOUD-DEPT",configuration=MySelfRule.class)

此处的MySelfRule是自定义的算法规则的配置类，示例代码如下：

package com.cyjz.irule;import com.netflix.loadbalancer.IRule;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** 作者 ZYL* 功能描述 : 自定义配置类Ribbon* 日期 2019/12/13 10:32  * 参数 null* 返回值 */
@Configuration
public class ZYLRule {@Beanpublic IRule myRule(){return new RandomRule_DIY();}
}

上面的 RandomRule_DIY()的示例代码如下：实现的功能是

问题：依旧轮询策略，但是加上新需求，每个服务器要求被调用5次。也即
以前是每台机器一次，现在是每台机器5次

package com.cyjz.irule;import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.AbstractLoadBalancerRule;
import com.netflix.loadbalancer.ILoadBalancer;
import com.netflix.loadbalancer.Server;import java.util.List;
import java.util.Random;public class RandomRule_DIY extends AbstractLoadBalancerRule{//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
////total = 0 //当total = 5以后，我们的指针才能往下走//index = 0 //当前对外提供服务的服务器地址//total需要重新置为零，但是已经达到过一个5次，我们的Index = 1//分析：我们5次，但是微服务只有8001，8002，8003三台//index到达3就要拉回来private int total = 0;private int currentIndex = 0;public Server choose(ILoadBalancer lb, Object key) {if (lb == null) {return null;} else {Server server = null;while(server == null) {if (Thread.interrupted()) {return null;}List<Server> upList = lb.getReachableServers();List<Server> allList = lb.getAllServers();int serverCount = allList.size();if (serverCount == 0) {return null;}if(total < 5){server = upList.get(currentIndex);total ++;}else{total = 0;currentIndex ++;if(currentIndex >= upList.size()){currentIndex = 0;}}if (server == null) {Thread.yield();} else {if (server.isAlive()) {return server;}server = null;Thread.yield();}}return server;}}public Server choose(Object key) {return this.choose(this.getLoadBalancer(), key);}public void initWithNiwsConfig(IClientConfig clientConfig) {}
}

2.注意：

官方文档明确给出了警告：
这个自定义配置类不能放在@ComponentScan所扫描的当前包下以及子包下，
否则我们自定义的这个配置类就会被所有的Ribbon客户端所共享，也就是说
我们达不到特殊化定制的目的了。

3.自定义算法的步骤：

1.从github上面获取随机算法的源代码：https://github.com/Netflix/ribbon/blob/master/ribbon-loadbalancer/src/main/java/com/netflix/loadbalancer/RandomRule.java

随机算法的源代码如下：

/*** Copyright 2013 Netflix, Inc.** Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.**/
package com.netflix.loadbalancer;import com.netflix.client.config.IClientConfig;import java.util.List;
import java.util.concurrent.ThreadLocalRandom;/*** A loadbalacing strategy that randomly distributes traffic amongst existing* servers.* * @author stonse* */
public class RandomRule extends AbstractLoadBalancerRule {/*** Randomly choose from all living servers*/@edu.umd.cs.findbugs.annotations.SuppressWarnings(value = "RCN_REDUNDANT_NULLCHECK_OF_NULL_VALUE")public Server choose(ILoadBalancer lb, Object key) {if (lb == null) {return null;}Server server = null;while (server == null) {if (Thread.interrupted()) {return null;}List<Server> upList = lb.getReachableServers();List<Server> allList = lb.getAllServers();int serverCount = allList.size();if (serverCount == 0) {/** No servers. End regardless of pass, because subsequent passes* only get more restrictive.*/return null;}int index = chooseRandomInt(serverCount);server = upList.get(index);if (server == null) {/** The only time this should happen is if the server list were* somehow trimmed. This is a transient condition. Retry after* yielding.*/Thread.yield();continue;}if (server.isAlive()) {return (server);}// Shouldn't actually happen.. but must be transient or a bug.server = null;Thread.yield();}return server;}protected int chooseRandomInt(int serverCount) {return ThreadLocalRandom.current().nextInt(serverCount);}@Overridepublic Server choose(Object key) {return choose(getLoadBalancer(), key);}
}

2.参考源码修改为我们需求要求的RandomRule_DIY.java，示例代码上面有显是

配置完成，可以测试