Please explain final AtomicReference

Question

can someone explain me this:

final AtomicReference<Integer> atomicReference = new AtomicReference<>(1);
atomicReference.set(2);

In what sense is final used?

Answer 1

In what sense is final used?

The variable itself is final. You can't change the variable's value to refer to a different AtomicReference object.

Calling set on the object and thus changing the data within the object isn't the same thing at all.

To put it in more real world terms, I can give you my home address and say, "You can't change where I live." That doesn't stop you from painting my front door green though (i.e. making a change to the house that the address refers to.)

Answer 2

final prevents you from changing the variable to refer to a different instance.
It does not prevent you from mutating the existing instance.

It means that you can't write

atomicReference = something;

Answer 3

final means that atomicReference can not reference another AtomicReference anymore.

Answer 4

final just means that the variable/object cannot be reassign.

But you can modify your object through setter for example

Check it out:

http://en.wikipedia.org/wiki/Final_(Java)