spring cloud Ribbon:自定义负载均衡

 自定义负载均衡算法

package com.kuang.myconfig;

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.concurrent.ThreadLocalRandom;

public class KuangRandomRule extends AbstractLoadBalancerRule {

//每个机器，访问5次，换下一个服务

//total=0，默认=0，如果等于5 我们指向下一个服务节点

//index=0 ，默认0，如果total=5 index++， 若index>3 则index=0

private int total=0;//被调用的次数

private int currentIndex=0;//当前是谁在提供服务

// @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 upList = lb.getReachableServers();//获得活着的服务

List allList = lb.getAllServers();//获得全部的服务

int serverCount = allList.size();

if (serverCount == 0) {

return null;

}

// int index = chooseRandomInt(serverCount);//生成区间随机数

// server = upList.get(index);//活着的服务去获得某一个

//=====================================================

if (total<5){

server = upList.get(currentIndex);

total++;

}else {

total=1;

currentIndex++;

if (currentIndex>upList.size()-1){

currentIndex=0;

}

server = upList.get(currentIndex);

}

//=====================================================

if (server == null) {

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);

}

@Override

public Server choose(Object key) {

return choose(getLoadBalancer(), key);

}

@Override

public void initWithNiwsConfig(IClientConfig clientConfig) {

// TODO Auto-generated method stub

}

}

Myconfig

package com.kuang.myconfig;

import com.netflix.loadbalancer.IRule;

import com.netflix.loadbalancer.RandomRule;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

@Configuration

public class KuangRule {

@Bean

public IRule myRule(){

return new KuangRandomRule();//默认是轮询；现在我们自定义为KuangRandomRule()

}

}

主启动类

package com.kuang.springcloud;

import com.kuang.myconfig.KuangRule;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

import org.springframework.cloud.netflix.ribbon.RibbonClient;

//Ribbon和Eureka 整合以后 ，客户端可以直接调用，不用关心IP地址和端口号~

@SpringBootApplication

@EnableEurekaClient

//在微服务启动的时候就能取加载我们自定义Ribbon类

@RibbonClient(name = "SPRINGCLOUD-PROVIDER-DEPT",configuration = KuangRule.class )

public class DeptConsumer80 {

public static void main(String[] args) {

SpringApplication.run(DeptConsumer80.class,args);

}

}

开启

Ribbon 实现负载均衡

相关链接