Deep Nesting (ARCH4184)

Key java.quality.deep-nesting · Severity warning · Category quality

Deeply nested if/for/while/try blocks hurt readability and raise the chance of bugs. Flatten conditions with early returns (guard clauses).

Incorrect

void handle(Order o) {
    if (o != null) {
        if (o.isPaid()) {
            if (o.items() != null) {
                for (Item i : o.items()) {
                    ship(i);
                }
            }
        }
    }
}

Correct

void handle(Order o) {
    if (o == null || !o.isPaid() || o.items() == null) return;
    for (Item i : o.items()) {
        ship(i);
    }
}

Fix

Flatten nesting with guard clauses and early returns; extract the inner block into a method if needed.