序列化之后出现null:null

[bobqian1007]

{"author":"test","creation_time":1710165916014,"directory_id":42,"parent_directory_id":-1,null:null,"name":"test1","space_id":1,"update_time":1710165916014}

使用fastjson版本1.2.83，序列化之后出现了key 为null的情况，想问下什么情况下会触发

[swapdewalkar]

如何复制