Yes, validation logic is definitely acceptable.
It should be noted though that if you have extensive validation you might want to extract this to a specific validator service. But for simple validations you can safely do this.
The entire idea behind using getters & setters is so nobody will have direct access to your fields. If you just wanted to set/get the value, you can make them public
.
Instead, we use setters to validate the incoming data and see if it complies with the rules we set.
This concept is also called "Encapsulation", a cornerstone of Object-Oriented Programming.