Question

I have an example like this

class A {

   A() {}
   public C createC () {
      ...
   }

} 

class B {

   B() {}
   public C createC () {

   }
}

Objects for A and B are created based an an

public enum D { ii, jj };

And I see code all over the place like

D d; 

switch (d) {
    case ii: (new A()).createC(); break;
    case jj: (new B()).createC(); break;
 };

How can I avoid the switch cases all over the place? I understand the code is not so clear.

Answer 1

I would be inclined to add the create code to the enum.

enum D {
    ii {
        public void createC() { new A().createC(); }
    },
    jj {
        public void createC() { new B().createC(); }
    };

    public abstract void createC();
}

You can then replace the switch with

d.createC();

Having said that I would also look at making the createC method static or moving the createC code to the enum rather than leaving it in the A and B classes.

If you make the createC method in A and B static the enum would look like

enum D {
    ii {
        public void createC() { A.createC(); }
    },
    jj {
        public void createC() { B.createC(); }
    };

    public abstract void createC();
}