Separate factories for empty model and model with data
I have some StateJson and some Model. State has data that may change and model can be recreated from state. The problem is don't understand how should i manage creating of my model? Should i make single factory that always takes json and create model from it? What should i do with default model creation than? Create "empty" json just to pass it to factory? Or have two factory methods for default creation and initializing from json? What is common practice for that case?

I have some StateJson
and some Model
.
State has data that may change and model can be recreated from state.
The problem is don't understand how should i manage creating of my model?
Should i make single factory that always takes json and create model from it? What should i do with default model creation than? Create "empty" json just to pass it to factory? Or have two factory methods for default creation and initializing from json?
What is common practice for that case?