a user-defined constructor of this class may have important logic in it that will be lost if someone called a generated no-arg one
This modifier annotation could be allowed only in data-classes that only define properties on constructor.
To create a entity model is more than sufficient.
This non arg constructor, when called, could late initializing all properties declared on primary constructor.
See my own post about this, over there I’ve explained better what is my propose: Feature request: A modifier annotation for data classes to provide a non arg constructor on JVM - #5 by llucca54