Jackson- JsonSerializable-什么时候应该实现serializeWithType方法

I am using JsonSerializable interface to customise my JSON output. I am able customise the JSON serialisation by overriding "serialize" method. But I wanted to know the scenarios where "serializeWithType" method is needed to be implemented as well. I could'nt find any examples where this method is being used. Can someone help me understand the need of this method with an example? Thanks in advance.I am using JsonSerializable interface to custom