IRule 默認提供有7種方式，使用輪詢方式

如何自定義

1:主啟動類加@RibbonClient

@RibbonClient(name="微服務名", configuration=MySelfRule.class)

也就是說MySelfRule.java不能和@SpringBootApplication註釋的類在同一包下.

MySelfRule.java

package com.atguigu.myrule;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RoundRobinRule;

@Configuration
 
public class MySelfRule
{
    @Bean
    public IRule myRule()
    {
        //return new RandomRule();// Ribbon默認是輪詢，我自定義為隨機
        //return new RoundRobinRule();// Ribbon默認是輪詢，我自定義為隨機
        
        return new RandomRule_ZY();// 我自定義為每臺機器5次
    }
}

package com.atguigu.myrule;

import java.util.List;

import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.AbstractLoadBalancerRule;
import com.netflix.loadbalancer.ILoadBalancer;
import com.netflix.loadbalancer.Server;

 
public class RandomRule_ZY extends AbstractLoadBalancerRule
{

    // total = 0 // 當total==5以後，我們指針才能往下走，
    // index = 0 // 當前對外提供服務的服務器地址，
    // total需要重新置為零，但是已經達到過一個5次，我們的index = 1
    // 分析：我們5次，但是微服務只有8001 8002 8003 三臺，OK？
    // 
    
    
    private int total = 0;             // 總共被調用的次數，目前要求每臺被調用5次
    private int
 
 currentIndex = 0;    // 當前提供服務的機器號

    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 = rand.nextInt(serverCount);// java.util.Random().nextInt(3);
//            server = upList.get(index);

            
//            private int total = 0;             // 總共被調用的次數，目前要求每臺被調用5次
//            private int currentIndex = 0;    // 當前提供服務的機器號
            if(total < 5)
            {
                server = upList.get(currentIndex);
                total++;
            }else {
                total = 0;
                currentIndex++;
                if(currentIndex >= upList.size())
                {
                  currentIndex = 0;
                }
            }            
            
            
            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;

    }

    @Override
    public Server choose(Object key)
    {
        return choose(getLoadBalancer(), key);
    }

    @Override
    public void initWithNiwsConfig(IClientConfig clientConfig)
    {
        // TODO Auto-generated method stub

    }

}

Srping cloud Ribbon 自定義負載均衡