Re: Enum mixin?

Robert Klemme <>
Sun, 23 Oct 2011 11:44:12 +0200
On 22.10.2011 01:16, markspace wrote:

On 10/21/2011 2:37 PM, Robert Klemme wrote:

On 21.10.2011 23:19, A. W. Dunstan wrote:

I'm ok with leaving it the way it is, but does anyone know of a better
approach? Preferably one that's not so complex that it's worse than my
current state of affairs?

I don't think it gets any better. Even if you go away from enums and
create an abstract base class etc. you'll have to do the typing for the
values plus you need to take care of serialization etc.

I would have thought that an abstract base class would get you what you
need. Maybe I'm overlooking something. The second class here seems to
remove a lot of boilerplate, esp considering my IDE will write the
constructor for me (since it's the only one available).

Well, for Al's original code you would also benefit from some IDE
boilerplate generation. Plus, if you rename the int property according
to sub class then you gain even less.

package quicktest;


public abstract class AbstactEnum implements Serializable {

For serialization to work like with enum (i.e. always only those
instances in memory that you define in the class) you need to do
considerably more. That effectively will be a reimplementation of enum.
  Plus, it can be tricky to get concurrency right etc. And you have the
drawback that you need to do it yourself.

 > ...

final class CloudModel extends AbstactEnum {

 > ...


I find that not really much less typing than the original code. Plus,
it's not an enum which means you lose the immediate information which
for example IDE's provide when showing an icon for the type of language

Kind regards


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