Enum class with name and ordinal constructors - kotlin

Question

Coming from java background, I'm wondering how do you handle Enums with string names and int ordinals.
I notice that property name and ordinal is built-in into enums as I tried to specify a constructor and it gave shadow warning. Here's my code.
enum class Department {
ACCOUNTING(0, "Accounting"),
SALES(1, "Sales"),
HR(2, "Human Resource")
}

Answer 1

From the documentation (bottom of the page):
Every enum constant has properties to obtain its name and position in the enum class declaration.
In your example that means that you can specify your enum as:
enum class Department {
ACCOUNTING,
SALES,
HR
}
Then
Department.values().forEach { println("${it.ordinal}: ${it.name}") }
will print
0: ACCOUNTING
1: SALES
2: HR
To add a display name (like "Human Resources") to your class, I think your best option is to add a property to your constructor:
enum class Department(val displayName: String) {
ACCOUNTING("Accounting"),
SALES("Sales"),
HR("Human Resources")
}
However, if you really want to stick to this short form, you could simply change the name accordingly:
enum class Department {
Accounting,
Sales,
`Human Resources`
}
Note the back ticks to allow for spaces in your display name. I would personally not do this, since Department.`Human Resources` is cumbersome to type and somewhat difficult to read (at least in my opinion).

Answer 2

You can override toString() for the specific enum class (HR) that you want to return a different value for. You can also override toString() for you parent enum and make it return a String with only the first letter capitalized, that way you can keep the naming convention intact.
enum class Department {
ACCOUNTING,
SALES,
HR {
override fun toString() = "Human Resource"
};
// capitalize first letter
override fun toString() =
super.toString().toLowerCase().capitalize()
}
you can then simply call toString() or pass it as string.
fun main() {
val hrString = HR.toString()
println(hrString) // Human Resource
println(HR) // Human Resource
println(ACCOUNTING) // Accounting
println(SALES) //Sales
}

Answer 3

Same as a class in kotlin, you can specify properties in the enum class constructor. For example
enum class Color( val r: Int, val g: Int, val b: Int){
RED(255, 0, 0), ORANGE(255, 165, 0), YELLOW(255, 255, 0);
}
As you already know Enum class(The common base class of all enum classes) have built in name and ordinal properties. these properties are defined as follows
/** Returns the name of this enum constant, exactly as declared in its enum declaration. */
public final val name: String
/** Returns the ordinal of this enumeration constant (its position in its enum declaration,
* where the initial constant is assigned an ordinal of zero). */
public final val ordinal: Int
Please note that they are marked final, meaning you can not override them.
So I suggest that instead of trying to change values of these properties as defined by the class, you should declare your own properties in the enum and use their values instead.