添加jason报错是由于版本问题
jar包jackson-databind和jackson-core,版本号是2.9.9.3版本,这个版本不会报这个错误
错误:
Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/exc/InvalidDefinitionException at org.springframework.beans.BeanUtils.instantiateClass (BeanUtils.jav
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.9.3</version>
</dependency>