Switch expressions

Code Comparison

String msg;
switch (day) {
    case MONDAY:
        msg = "Start";
        break;
    case FRIDAY:
        msg = "End";
        break;
    default:
        msg = "Mid";
}

String msg = switch (day) {
    case MONDAY  -> "Start";
    case FRIDAY  -> "End";
    default      -> "Mid";
};

Why the modern way wins

🎯

Returns a value

Assign the switch result directly — no temporary variable needed.

🛡️

No fall-through

Arrow syntax eliminates accidental fall-through bugs from missing break.

✅

Exhaustiveness check

The compiler ensures all cases are covered.

Old Approach

Switch Statement

Modern Approach

Switch Expression

JDK Support

Switch expressions

Available

Widely available since JDK 14 (March 2020)

How it works

Switch expressions return a value directly, use arrow syntax to prevent fall-through bugs, and the compiler verifies exhaustiveness. This replaces the error-prone statement form.