I have a class called Base which has a method called execute(). There are about 100 classes which derive from this base class and provide their own implementation of execute(). Now, I have some common logic which I want to put in Base.SomeMethod(). This method needs to be called at the end of execute(). My question whether it is possible to call this without changing each and every derived class's execute() method?

• java
• oop

public class Base {
    public final void execute() {
        doExecute();
        someMethod();
    }

    protected abstract void doExecute();

    public void someMethod() {
    }
}

This solution prevents the super code smell.

Yes, but you have to change the callers then. Callers will have to call a doExecute() (find a better name for it though) method, which you define in your base class as final, and which calls execute(), then the common code.

Another option is aspect-oriented programming, but I wouldn't recommend it for this purpose, that is, to "hack" code.

The question is: why is changing the name of a method in a 100 or so classes such a problem? It's a click of the mouse with an IDE.

Not that I'm aware of. Next time you should consider that you might want to add some common action for all extended classes, and call for super.execute()!

Only by using something that instruments your code; this isn't possible with pure Java.

Let me state your problem as i understand : Animal class has Breath() method which has implementation and due to inheritance all the subclasses has this member and unless there is very different way of breathing nobody will override.

Now at the end of Breath method you want to call CloseEyes() method of animal class and may be that is true that some or all of the subclasses overrides CloseEyes() method.

So your problem : Everytime any animal breath you want to them to CloseEyes but from Animal class and not from the derived classes.

1. If there are already CloseEyes() methods in many derived classes then you are actually doing something wrong in calling base class's CloseEyes().

2. If you still want only base class's method to be called then why do you need same method name- you just say AnimalEyeClose() , make it private and have it in Animal class.