Module 02 · SOLID and friends · Drill

SOLID drill

Scenario prompts that check whether solid and friends is usable under pressure. Answer out loud, then compare.

4 prompts25 minNew

0 of 4 graded

Prompt 1
A ReportService class loads sales data with raw SQL, computes totals and tax, formats PDF and Excel output with a switch on format, emails the result and logs to a file. Walk through which SOLID principles it violates and refactor it, naming the classes and interfaces you would end up with.
Say your answer out loud first. Thirty seconds is enough.
Prompt 2
A Storage interface has read, write, delete and listVersions. The team adds a ReadOnlyArchiveStorage that throws UnsupportedOperationException on write and delete, and a CdnStorage that does not support listVersions. Callers now wrap calls in try/catch and instanceof checks. Diagnose and fix the design.
Say your answer out loud first. Thirty seconds is enough.
Prompt 3
A shipping-cost calculator has an if-else chain over carriers (UPS, FedEx, DHL, local courier), each branch calling a vendor SDK directly, and the chain is copied into checkout and returns. Product will add two carriers next quarter. Refactor it with open-closed and dependency inversion, and say what you would deliberately not abstract.
Say your answer out loud first. Thirty seconds is enough.
Prompt 4
In code review you see: invoice.getCustomer().getAccount().getBillingAddress().getCountry().getVatRate() used in six places, a shared formatName(user, isAdmin, isShort, isLegal, locale) helper with growing flags, and an abstract BaseEntityManager with 40 methods 'for future needs'. Name the principle each one breaks and the fix.
Say your answer out loud first. Thirty seconds is enough.