The best way to compare enums

Question

I have an enum, for example enum Color { Red, Brown }. I also have some variables of that type:

Color c1 = Brown, c2 = Red

What is best way to compare to a constant value:

if (c1 == Color.Brown) { 
    //is brown
}

or

if (c1.equals(Color.Brown)) {
    //is brown
}

Either is fine, but I think for simplicity's sake, I go with ==. — Hovercraft Full Of Eels, Jul 29 '11 at 15:48
I prefer to put the constant on the left. That way if you accidentally put = you get a compiler error. Color.Brown==c1 — QuentinUK, Jul 29 '11 at 15:59
http://stackoverflow.com/questions/1750435/comparing-java-enum-members-or-equals — Md Faraz, Aug 12 '16 at 06:26
FYI, anyone interested in this Question may find the [`EnumSet`](https://docs.oracle.com/javase/10/docs/api/java/util/EnumSet.html) and `EnumMap` classes useful. — Basil Bourque, Oct 29 '18 at 02:56
`equals` accepts an `Object` and so there is less type safety compared to `==` — WW., Feb 23 '21 at 03:33

score 13 · Answer 1 · answered Jul 29 '11 at 15:47

13

Use ==. There cannot be multiple instances of the same enum constant (within the context of a classloader, but let's ignore that point) so it's always safe.

That said, using equals() is safe too, and will perform reference equality as well. It's pretty much a style choice.

Personally I very seldom find myself using if statements for enums at all. I favour switch blocks.

switch (c1) {
    case Brown:
        //is brown
        break;
    case Red:
        //...
}

answered Jul 29 '11 at 15:47

Mark Peters

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That code snippet makes me a sad panda. D: – Moonbeam Jul 29 '11 at 15:54
1

@Moonbeam: Why is that? Obviously it's a contrived example, but it's the OP's example, not mine. – Mark Peters Jul 29 '11 at 15:57
3

Use == because enums variables are allowed to be null. There is no reason IMO to use equals() – Mike Q Jul 29 '11 at 16:06

The best way to compare enums

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