title: How to add extra fields to an Object during Jackson's json serialization?
body: <p>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).</p>
  
  <p>What is the best way of doing that, which doesn't involve creation of custom serializer class, which will take care of serializing of whole set of object's fields? Or may be it is possible to inherit some "basic" serializer, and simply take it's output and add new field to it somehow?</p>
  
  <p>I learned about <a href="http://wiki.fasterxml.com/JacksonMixInAnnotations">mixins</a>, and looks like it is possible to rename/hide some fields, however it seems not be possible to add an extra one.</p>