最开始运行时报错

bean of type 'com.netflix.client.config.IClientConfig' that could not be found.

• 在网上查找方法 创建 RibbonConfiguration 类继承 IClientConfig
• 这个类是不能创建的，项目可以正常运行，可一旦用手 Fegin 客户端调用就会报空指针异常，返回的 message 如下

Error creating bean with name 'httpClientConnectionManager' defined in 
org.springframework.cloud.netflix.ribbon.apache.HttpClientRibbonConfiguration$ApacheHttpClientConfiguration: 
Bean instantiation via factory method failed; nested exception is 
org.springframework.beans.BeanInstantiationException: Failed to instantiate 
[org.apache.http.conn.HttpClientConnectionManager]: Factory method 'httpClientConnectionManager' threw 
exception; nested exception is java.lang.NullPointerException

错误原因

• 报这个错误是因为使用Nacos注册中心时 引入的依赖有关

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-alibaba-nacos-discovery</artifactId>
    <version>2.1.1.RELEASE</version>
</dependency>

将依赖改为

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    <version>0.9.0.RELEASE</version>
</dependency>

问题解决