Java entity - why do I need an empty constructor?

Question

This might sound stupid to you, but why do I need to define an empty constructor in my @Entitys?

Every tutorial I saw said : every entity needs an empty

Answer 1

From the JPA tag, I suppose that you are working with Java beans. Every bean needs to have the following properties:

1. Getters and setters for all its main instance variables.

2. An empty constructor.

3. All its instance variables should preferably be private.

Thus the statement : "every entity needs an empty constructor".