Question

I'd like to load a series of Swing Actions into a container at runtime and access them by a constant name as is possible with an Enum. The purpose of this would be to both restrict the Actions possible and also improve readability.

Initially, I was considering a sort of dynamic enum (see http://blog.xebia.com/2009/04/02/dynamic-enums-in-java/) but as Java Drinker points out below this is unnecessary since the actions remain unchanged.

Ideally, what I'd like to do is a sort of wrapper that contains AbstractAction instances which could be enabled/disabled and be able to refer to each action through a symbolic name.

Edit: Question has been reformulated.

Was it helpful?

Solution

You can do something like this:

public enum Actions {
    COPY( new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            //do something
        }
    }),
    PASTE( new PasteAction() );

    public final AbstractAction action;
    private Actions(AbstractAction action) {
        this.action = action;
    }

}

//...
Actions.COPY.action...;

And then as others have said, use the enum in conjunction with an EnumSet or EnumMap. Personally, I don't see a huge value in it over just having a few named fields without an enum.

I think what you really want is some kind of Action registry like this:

public class ActionsManager {
    private final Map<String, Action> actions;
    private final Map<User, Set<String>> enabledActions;
    public Action get(String id);
    public void register(String id, Action action);
    public void deregister(String id);
    public boolean isEnabled(User user, Action action);
}

Implementation left as an exercise.

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