aaronfude@gmail.com wrote On 02/10/06 16:19,:

   Yes, it's a little more typing.  On the other
hand, it creates namespaces.  Thus, you avoid
conflicts between names that belong to different
enums but happen to look the same.  Paraphrasing
Bloch's "Effective Java:"

    enum Orange { NAVEL, VALENCIA, BLOOD };
    enum Fluid { BLOOD, SWEAT, TEARS };

   (Sorry to hear that your pet has the mange and
needs to be refurred.)

You are not allowed to do that. The types are nailed down at compile
time.  The constructors are private.  If you want new Pet types you
have to add them to the Pet class.

You are only allowed to write

Pet pet = Pet.DOG;

   I don't think the goal of enums was to save typing, so it shouldn't be
surprising that you need more typing when using enums (nor should it be
surprising that you need less typing for that matter; it's somewhat
irrelevant to the design goals).

   - Oliver

import static xyz.Pet.Type.*;

Pet pet = new Pet(DOG, "Sparky");

Or even:

enum PetType {
   DOG, CAT, SNAKE;
   public Pet create(String name) {
       return new Pet(this, name);
   }
}

import static xyz.PetType.*;

Pet pet = DOG.create("Sparky");

pet.dispose();

Tom Hawtin

With the new syntax you can go several ways:
1. Type does NOT have to be nested in Pet, so
all could be in the same vet package so
that a simple

import vet.*;

would allow references to Pet and references to
Species (assuming it's better not to have an
overly generic name like Type running around).

You can then also use the new
import static vet.Species;
or if you love the nested-class
import static vet.Pet.Species;

and then you CAN reference
DOG, CAT and SNAKE with less syntax then
before.

I managed to get the following line to compile:

Pet myPet = new Pet(DOG, "Sparky");

With
a. a class Species
b. a class Pet
c. a static import

It is the static import which gives you shortened syntax.

import static; It's not just for java.lang.Math!

-Paul