Working with Enums

An enum (short for “enumeration”) defines a fixed, named set of constants. Use it whenever a value should only ever be one of a small, known list of options.

Tip: reach for an enum instead of a plain String whenever a value has a fixed set of valid options, like a day of the week or an order status — it lets the compiler catch typos for you.

Defining an enum

public enum OrderStatus {
    PENDING,
    SHIPPED,
    DELIVERED,
    CANCELLED
}

Using an enum

OrderStatus status = OrderStatus.SHIPPED;

if (status == OrderStatus.SHIPPED) {
    System.out.println("Your order is on its way!");
}

Unlike a plain String, the compiler guarantees status can only ever be one of the four defined constants — there’s no risk of a typo like "SHIPED" slipping through unnoticed.

What’s next

Next: Record, a modern Java class type designed specifically for holding immutable data.