Anybody know how to use "enum" in Java?

[Jon Campbell]

The following code compiles, but I don't have any documentation on how to use the "enum" structure. I cant find any info on it in my books or Sun's language documentation...

class Test {

enum eone {
Plus { int operate(int x) { return ++x;} },
Minus { int operate(int x) { return --x;} }
}


public static void main (String[] args){
System.out.println("eone="+eone.Plus);
}

}

[Jim Yingst]

http://java.sun.com/j2se/1.5.0/docs/relnotes/features.html#enums

[Ilja Preuss]

To make the enum really useful, it's missing an abstract method declaration:

enum eone {
  Plus { int operate(int x) { return ++x;} },
  Minus { int operate(int x) { return --x;} };
 
  abstract int operate(int x);
}

You can use that enum like a normal class, with Plus and Minus being final static fields of the type eone (in fact that's what it *is*).

[Barry Gaunt]

Have you read Sun's Enum Tutorial?