Re: Enums: Properties vs. Methods

Wanja Gayk <>
Sat, 2 Apr 2011 11:23:00 +0200
In article <2f38bb8e-9a8d-4464-ad3d-b9ce0b557219>, says...


I am just musing about the pros and cons of using boolean properties
in enum classes vs. custom methods.
 So far I found

pro Properties:
- less classes
- when adding enum values to an enum you cannot forget to define

pro Methods:
- smaller memory footprint per instance

Quite frankly: Use what's easier to read and maintain.
Memory and runtime should be your smallest concern, assuming you use
some common sense when chosing your algorithm, only if there's clearly a
problem for the user and the system you should optimize to something
probably less readable. To find bottlenecks, don't guess, but use a
profiling tool. "jvisualvm" (which you can find in your jdk/bin folder)
is not bad for a start.

  /** We use boolean properties. */
  public enum Prop {

    A(true, true), B(true, false), C(false, true);

    private final boolean a;

    private final boolean b;

    Prop(boolean a, boolean b) {
      this.a = a;
      this.b = b;

    public boolean isA() {
      return a;

    public boolean isB() {
      return b;

Like proposed elsewhere you could also write (untested):

   public enum Prop {
       public boolean isA(){return true;}
       public boolean isB(){return true;}

       public boolean isA(){return true;}
       public boolean isB(){return false;}
       public boolean isA(){return false;}
       public boolean isB(){return true;}

     public abstract boolean isA();
     public abstract boolean isB();

Consider that the use of boolean parameters is often quite bad to read
and maintain. Just have a look at your boolean initializer:

  A(true, true), B(true, false), C(false, true);

You can't tell from looking at the code, whether the first argument
represents the return value for "isA" or "isB". From this point of view,
with a proper formatting, I'd prefer the abstract method approach.

Regarding the use of boolean parameters I have, some time ago written, a
blog you might like to read:

Kind regards,

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dangerously - and I can assure you from having been teammate to
Jean Alesi and knowing what kind of cars that he can pull up with,
when Jean Alesi says that a car is dangerous - it is. [Jonathan Palmer]

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