将JSON内容包含在将由Jackson Mapper序列化的对象中的最佳方法

I am using Jackson Mapper object to marshal objects into JSON. It works great but sometimes I need to include some specific JSON that is not really a property of the object to be marshalled. If I create a String property like "extraJSON" and put JSON content there, when that object is marshalled extraJSON will be escaped, so ends up being some kind of JSON inside JSON. I have tried creating a property of type JsonObject (Java 8 JSON) but is not marshalled correctly.I am using Jackson Mapper object to marshal obj