该异常是由 swagger 引起的

解决方法：忽略原版本的swagger-annotations和swagger-models，添加1.5.21版本的

 <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger-ui</artifactId>
                <version>2.9.2</version>
                <exclusions>
                    <exclusion>
                        <groupId>io.swagger</groupId>
                        <artifactId>swagger-annotations</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>io.swagger</groupId>
                        <artifactId>swagger-models</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>io.swagger</groupId>
                <artifactId>swagger-annotations</artifactId>
                <version>1.5.21</version>
            </dependency>
            <dependency>
                <groupId>io.swagger</groupId>
                <artifactId>swagger-models</artifactId>
                <version>1.5.21</version>
            </dependency>