AtomicInteger的使用之一
    

package com.xx.springcloud.LB;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLB implements LoadBalancer
{
    private AtomicInteger atomicInteger = new AtomicInteger(0);

    public final int getAndIncrement()
    {
        int current;
        int next;
        do
        {
            current = atomicInteger.get();
            next = current >= Integer.MAX_VALUE ? 0 : current + 1;
        }while (!atomicInteger.compareAndSet(current,next));
        System.out.println("*******第几次访问，次数next: "+next);
        return next;
    }
    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances)
    {
        //得到服务器的下标位置
        int index = getAndIncrement() % serviceInstances.size();
        return serviceInstances.get(index);
    }
}