How to set data type of enum class?

Question

I am creating an enum class in java, which is already created in .NET.

This is .NET code.

public enum Bezel : byte
        {
            Flashing,
            SolidOn,
            None = 254
        }

And this is Java code i am trying.

public enum Bezel {

        Flashing,
        SolidOn,
        None = 254
    }

In the .NET code, they are extending "byte". So, how can we do the same in Java?

Answer 1

Enums in java are sets of objects, not sets of constants as they are in C#. So, you need to write your enum in java like this:

public enum Bezel 
(
    Flashing(0),
    SolidOn(1),
    None(254);

    public final int value;
    public Bezel( int value )
    {
        this.value = value;
    }
)

Then, when you need the actual value, do this:

Bezel b = ...;
int value = b.value;

Answer 2

Enums in Java and .NET are very different. In .NET, they're just named numbers, basically. In Java they're a fixed set of objects - which you can give extra behaviour etc.

Also, the C# code isn't "extending" byte - it's just using byte as the underlying type. The nearest equivalent Java code would be something like:

public enum Bezel {
    // Note different naming convention in Java
    FLASHING((byte) 0),
    SOLID_ON((byte) 1),
    NONE((byte) 254);

    private final byte value;

    private Bezel(byte value) {
        this.value = value;
    }

    public byte getValue() {
        return value;
    }
}

Note that if you print out Bezel.NONE.getValue() , it will print -2, because Java's byte type is signed whereas it's unsigned in C#. There's no unsigned byte type in Java - but you could always use short or int instead, to cover the 0-255 range (and more, of course).

You may also want a method to retrieve a Bezel given its value - something you could do in C# just by casting. We don't know how you're going to use the enum though.