Question

I often see constructors like this

public class A {

   private int b;

   public A(int b) {
      setB(b);
   }

   public void setB(int b) {
      this.b = b;
   }
}

Is this a good idea? Should I use setter methods in the constructor? Isn’t it a problem if I would override either the constructor or the setter methods in a sub class?

Answer 1

It’s probably not a good idea. If you don’t make that class final and don’t make the setName( … ) method private or final someone else is able to extend your class and overrid the setName( … ) method. Your constructor (in your base class) will call that method in the extending class instead of your implementation. Nobody knows what that method can do. As a rule of thumb: a constructor shouldn’t call methods that can be overriden.