Switch expressions

Definition

A switch expression returns a value and uses ->, so there is no fall-through and no break. The compiler checks that every case is covered, which makes it safer than the old switch statement.

Example code

Turning a day into a number of hours

enum Day { MON, TUE, WED, THU, FRI, SAT, SUN }

class Demo {
    static int workHours(Day day) {
        return switch (day) {
            case MON, TUE, WED, THU -> 8;
            case FRI -> 6;
            case SAT, SUN -> 0;            // if a case is missing, it does not compile
        };
    }

    public static void main(String[] args) {
        for (Day day : Day.values()) {
            System.out.println(day + ": " + workHours(day));
        }
    }
}

// Output:
// MON: 8
// TUE: 8
// WED: 8
// THU: 8
// FRI: 6
// SAT: 0
// SUN: 0