nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of {class}
no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 1, column: 2]클래스에 default constructor 만들어주면 됨
우당탕탕