Why specify an empty constructor?

Question

Java

I read Schildt and there was such question. As I understand it, this is one of the ways to implement polymorphism and inheritance in JAVA, but still an empty constructor - it does not carry any information, why then specify it at the beginning of the class?

Answer 1

sometimes it is necessary for code generators and libraries to work, for example, for ormlite to work, you need to describe an empty constructor in the model, but in the general case this is not necessary