Suppose you use constant strings (or int
values - the same goes for them):
// Constants for player types
public static final String ARCHER = "Archer";
public static final String WARRIOR = "Warrior";
// Constants for genders
public static final String MALE = "Male";
public static final String FEMALE = "Female";
then you end up not really knowing the type of your data - leading to potentially incorrect code:
String playerType = Constants.MALE;
If you use enums, that would end up as:
// Compile-time error - incompatible types!
PlayerType playerType = Gender.MALE;
Likewise, enums give a restricted set of values:
String playerType = "Fred"; // Hang on, that's not one we know about...
vs
PlayerType playerType = "Fred"; // Nope, that doesn't work. Bang!
Additionally, enums in Java can have more information associated with them, and can also have behaviour. Much better all round.
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