杰克逊::在序列化中为对象添加额外的字段

I need to add new property to an object, when serializing to JSON. The value for the property is calculated on runtime and does not exist in the object. Also the same object can be used for creation of different JSON with different set ot fields (kind of having a base class with subclasses, but I don't want to create ones just for JSON generation).I need to add new property to an object, when s