Clean Code with Java: Learn Simple Design, Refactoring & TDD

Discover the four principles of simple design—runs all tests, minimize duplication, maximize clarity, and keep it small—enabled by automated tests and agile refactoring.

Apply the four principles of simple design to isGradeB, improving clarity and reducing duplication by refactoring with extract constants, a maths-specific upper limit, and unit tests validate the solution.

Refactor the getGrade logic to reduce duplication and improve clarity by inlining methods, using constants, and aligning with business rules. Consider enum-based grades while keeping tests green.

Refactor the StudentHelper.willQualifyForQuiz method to eliminate duplication, extract small boolean helpers like isNotGood and isGood, and introduce an extraLimit constant to clarify business logic and improve readability.

Naming stands as the most difficult programming challenge, guiding variable, method, class, package, and API names; balance name length with scope and follow Java and project conventions.

Implement text helper to swap the last two characters and verify with the JUnit test. Apply four principles of simple design using readable variables and safe handling for short strings.

Learn when and why to use comments in Java, including API comments (Javadoc), type two notes, and to-dos or fix me reminders to keep code clear.

Implement TextHelper.truncateAInFirst2Positions to remove A's from first two characters using first2Characters and restOfTheString. Validate with TextHelperTest and JUnit tests, and consider refactoring with a replaceAll helper and a 2 constant.

Learn to apply simple design principles to refactor a unit test for CustomerBO, highlighting important values, extracting methods, and building a generic createProductsWithAmounts using an amounts array and streams.

Refactor and test the CustomerBO product sum method, handling euro and Indian rupee currencies, and assert exceptions like DifferentCurrenciesException with JUnit 5.

Adopt a clean code mindset by prioritizing unit tests, writing tests before code, refactoring with tests, and running tests continuously through continuous integration to catch defects early.

Explore five key unit testing principles to write easy-to-understand tests that fail only on production defects, minimize duplication, test all edges, and run quickly using mocks and clear naming.

Embrace a growth mindset by treating challenges as opportunities to grow, learn from constructive feedback, celebrate effort, and stay curious, recognizing hard work pays off over the long term.

Learn refactoring as restructuring code without changing functionality, focusing on the sequence of small steps and practicing with unit tests, aided by infinitest.

Refactor the getCustomerProductsSum method by extracting submethods, using streams to sum product amounts, and validating that all currencies match the first product currency, with Infinitest enabling continuous testing.

Refactor the Movie.isValidRating method to simplify logic, extract low level and high level helpers, and adopt a concise rating list with isValidBRating and isValidARating.

refactor the MenuAccess logic to simplify access checks for menu items, replacing nested conditionals with stream-based role checks, extracting helpers, and validating changes with MenuAccessTest.

Refactor the user login checker by renaming variables, extracting write and read lock methods, and simplifying conditions while using an infinite test to validate improvements.

Refactor a login lock mechanism by simplifying conditions, extracting variables and methods, and choosing write or read locks based on user id, time elapsed, and first screen.

Learn ten practical tips for becoming a good programmer, including pair programming, the Boy Scout rule, continuous learning, touch typing, IDE shortcuts, asking why, and exploring languages and programming approaches.

Learn test driven development by practicing red, green, and refactor: write a failing test, implement the simplest code to pass, and refactor while keeping tests green.

Practice test-driven development by building a StringHelper that removes A in the first two positions, using red-green-refactor cycles, JUnit5 tests, and step-by-step tdd exercises from the tdd.md.

Reinforce test-driven development through practical practice with StringHelper.replaceAInFirst2Positions, guiding handling of empty strings and other test scenarios, and building the TDD habit via small, iterative tests.

Explore test driven development by implementing a string helper that checks if the first two and last two characters are the same, using red-green-refactor cycles and evolving tests.

Practice the bowling kata to implement a bowling game using test-driven development, learning frames, rolls, spares, strikes, and the scoring bonuses across ten frames.

learn to apply test driven development to a bowling kata by writing JUnit tests, implementing a game with roll and score, and refactoring with red-green-refactor in Eclipse.

The lecture demonstrates TDD for the bowling kata, introducing a spare scenario, refactoring to store all rolls in an array, and managing frames and roll bonuses.

Advance test-driven development by adding tests for two spares and a strike in the bowling kata, refine bonuses, and refactor by moving logic into a Game class.

Unlearn old approaches, practice TDD with additional challenges, and pair program with an experienced mentor to establish the TDD habit in two to three months.

Deep work creates flow, boosting efficiency and rapid learning of complex concepts. Build it with an interruption-free environment and dedicated two to three hours per week for deep work sessions.

Celebrate your hands-on progress in clean code, share success stories, invite others to learn with you, and continue the journey with Code Complete, The Pragmatic Programmer, and Effective Java.

Discover how Java has evolved into a modern, cloud native, container ready language with features like lambda expressions, modularization, records, pattern matching, and virtual threads, enabling fast, scalable applications.

Explore the primary goals behind recent Java releases, highlighting concise code with records, switch expressions, and cloud-ready containers. Learn about improved concurrency with virtual threads, productivity boosts, and backward compatibility.

Take a 10,000-feet overview of major Java versions and their key features, including enhanced for loops, generics, enums, autoboxing, streams, lambdas, var inference, switch expressions, text blocks, and pattern matching.