John B. Matthews wrote:
In article
<24ebe868-e3b3-49f9-a23c-0c47a107d6fe@a32g2000yqm.googlegroups.com>,
"david.karr" <davidmichaelkarr@gmail.com> wrote:
On Dec 18, 4:25 pm, EJP <esmond.not.p...@not.bigpond.com> wrote:
david.karr wrote:
Can someone think of a better way to do this, that doesn't repeat
the column values?
Have each enum value enter itself on construction into a
Map<Integer, YourEnum> with its own ColumnValue as the key.
Like Peter I cannot see the point of setColumnValue(), and the Map
would of course require the columnValue to be constant.
Yes, you're right, there's no need for "setColumnValue()".
Concerning the Map, I had already thought of that. That's the
obvious way to do it. Now, how would you do it? I would assume
you'd define a static Map in the enum type and have the constructor
put itself into the map. The problem is, it doesn't appear to be
possible to do that. It doesn't compile.
A static initializer works, as suggested in the "enum Color" discussion:
<http://java.sun.com/docs/books/jls/third_edition/html/classes.html#8.9>
Here's a similar example that constructs a Map<Integer, Key>, where
Integer is a keyCode and Key is an enum:
<http://robotchase.svn.sourceforge.net/viewvc/robotchase/trunk/
src/org/gcs/robot/Key.java?revision=27&view=markup>
The mapping is persisted using java.util.prefs.Preferences rather than a
database, but the result is similar.
What might work is implementing some sort of "super-map" that holds
all the mappings for all enum types you implement, so the key would
have to concatenate the class and the custom ordinal.