Re: Class Constants - pros and cons

Robert Klemme <>
Wed, 28 Jul 2010 16:45:21 +0200
On 25.07.2010 16:39, Lew wrote:

Magnus Warker a =E9crit :

Don't top-post!

It's the readibility of the code.

With constant classes I can write something like this:

public void setColor (Color color)
if (color == Color.WHITE)

No. That would be a bug. You'd write 'if ( color.equals( Color.WHITE ) =


That depends on the rest of Color's class definition (whether there are
public constructors, whether the class is serializable and whether
custom deserialization is in place - all stuff someone who makes this an =

enum does not have to take care of manually btw). For enums (whether as =

language construct or properly implemented although this is a bad idea
since Java 5 IMHO) I would rather use "==" here because it is more
efficient and stands out visually.

Since enums are classes, they can contain behavior. That means you won'=


need if-chains nor case constructs to select behavior; just invoke the
method directly from the enum constant itself and voil=E0!

One can even have custom code *per enum value* which makes implementing
state patterns a breeze. See

Kind regards


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