Why can the value of final be changed?

Question

Java

I understand that this block of code acts as a counter, but I don't understand why
Gjxt

Answer 1

It cannot be changed (you cannot change the link). And in this example, it is not changed, but the incremented value of counter is written into it.

Answer 2

So counter is not final. Here final is the value of id.

Answer 3

You cannot change final fields after the object is created, but you can and should change them (set values ​​for them) during the creation of the object. So there are no problems here. During the creation of the object, before calling the constructor, all fields are initialized, including this id field.