Right way to compose an action as a sequence of multiple smaller actions?

Question

I have three actions defined like so:

public class A extends AbstractAction;
public class B extends AbstractAction;
public class C extends AbstractAction;

Now I want to define a jumbo action that does these three actions in order. I am sure there is a better way to do this than to do the following:

public class JumboAction extends AbstractAction {

  ...

  public void actionPerformed(ActionEvent e) {
    new A().actionPerformed(null);
    new B().actionPerformed(null);
    new C().actionPerformed(null);
  }
}

I just dont know what the better way is. Can someone please point me to that?

To add more context as suggested in answers, my application has some UI elements (like nodes and edges), and the user can select a bunch of nodes and perform A, B, C, or JumboAction on them.

I think you've abstracted away too much of the problem for us to make sense of this. If you know statically which actions you want to perform and in what order, why are you doing all this work to make them dynamic instead of just hard-coding them as methods you can call? — DaoWen, Sep 09 '13 at 03:09
It almost sounds as if you want to push a variable number of ActionListeners onto a Queue. — Hovercraft Full Of Eels, Sep 09 '13 at 03:18
You can just add a `List` to `JumboAction` or its superclass — kolossus, Sep 09 '13 at 03:21

score 0 · Answer 1 · answered Sep 09 '13 at 03:01

0

This idea of one control calling others as you're doing doesn't smell right to me, as if you're confusing the control with the model (ignoring also your use of null for the ActionEvents). The control should change the state of the model by calling model methods. Why not have your jumbo control call three (or more) model methods or whatever else is required, in order to complete its needs.

Perhaps you can give us a better understanding of your problem by giving more information about the concrete specifics of your problem as they may be just as or more important than the abstract ideas.

answered Sep 09 '13 at 03:01

Hovercraft Full Of Eels

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Because the three smaller actions can be called individually too, and I do not want to duplicate code! – Moeb Sep 09 '13 at 03:01
1

@Moeb: I think that you may wish to make your question less abstract and more concrete. What *specifically* are you trying to do with this idea? What problem is driving this question? – Hovercraft Full Of Eels Sep 09 '13 at 03:02
Added more explanation to the question. – Moeb Sep 09 '13 at 03:05

score 0 · Answer 2 · answered Sep 09 '13 at 03:03

The way you're doing it is just fine.

The only thing I would do differently is replace actionPerformed(null) with actionPerformed(e). This would allow for A, B, and C to access the ActionEvent in context.

edit: If actions A, B, and C were not intended to be used individually as well, I would recommend combining the actions into three methods within the JumboAction class.

score 0 · Answer 3 · answered Sep 09 '13 at 03:07

It seem to me that you are going outside the purpose of the Action classes because you are passing null to the actionPerformed methods.

Consider encapsulating your execution logic (business or otherwise) in a separate set of classes class and call those from the actions.

It will remove the need to duplicate the code and give you cleaner Action classes that do what they are supposed to do.

You can if you wish to use the same order have another method calling the business logic classes in an pre defined order.

Also check out the Command pattern, particularly the macro command area. Perhaps you can benefit from some adaptation of that.

Right way to compose an action as a sequence of multiple smaller actions?

3 Answers3