AbstractMethodError

分布式系统feign调用报错：

java.lang.AbstractMethodError: org.springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient.choose(Ljava/lang/String;Lorg/springframework/cloud/client/loadbalancer/Request;)
Lorg/springframework/cloud/client/ServiceInstance;

主要原因是还是jar包冲突,nacos依赖的ribbon和springcloud的ribbon存在同个方法的不同实现，不兼容。
排除掉nacos的spring-cloud-starter-netflix-ribbon依赖：

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
	    <exclusions>
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
	    	</exclusion>
            </exclusions>
        </dependency>