Long Method (ARCH4180)

Key java.quality.long-method · Severity info · Category quality

Overly long methods take on more than one responsibility and become hard to read and test. Split the logic into well-named helper methods.

Incorrect

void processOrder(Order o) {
    validate(o);
    // 40+ lines: pricing, tax, discount,
    // inventory deduction, invoice, email, logging...
    double tax = o.total() * 0.18;
    double discount = o.total() > 1000 ? 0.1 : 0;
    inventory.deduct(o.items());
    invoices.create(o, tax, discount);
    mailer.send(o.customerEmail(), buildBody(o));
    audit.log("order " + o.id());
}

Correct

void processOrder(Order o) {
    validate(o);
    Pricing p = price(o);
    inventory.deduct(o.items());
    invoices.create(o, p);
    notify(o);
}

Fix

Break the method into small, named helpers that each do one thing.