Refactoring Legacy Code: Antipatterns to SOLID Principles

Learn the open closed principle: write code that is open for extension but closed for modification, using base classes and inheritance to extend functionality while keeping maintainability and reusability.

Understand the Liskov substitution principle, where subclasses replace a parent class without breaking behavior. The bird example shows why mismatched capabilities break code and how LSP enables reliable software.

Demonstrates the golden hammer anti-pattern in a C# example that sums ages and finds developers, then refactors to use built-in list methods for cleaner and more efficient code.

Explore the golden hammer antipattern in Python, solving tasks with for loops, then refactor using built-in functions like sum, max, and filter with lambda for cleaner, maintainable code.

Explore the god object antipattern in dotnet and refactor into focused classes for user, product, payment, and shipping to uphold the single responsibility principle and reorganize responsibilities.

In this lecture, we analyze a Python god object example for an e-commerce site, and refactor it into four classes: user, product, payments, and shipping, to isolate responsibilities.

Explore copy paste syndrome, its causes and consequences, and learn refactoring and best practices to reduce technical debt, improve modularity, and use code analysis tools and pair programming.

Explore how copy-paste coding leads to unreadable CSV read, process, and write scripts, then refactor to read CSV data, calculate row averages, and write results to a new CSV.

Identify and fix the copy-paste anti-pattern in a c# csv workflow by refactoring ad hoc code into a function that calculates averages and reads, processes, and writes csv data.

Explore a lava flow anti-pattern in JavaScript by refactoring a calculator function to remove unused variables, deprecated code, and unreachable branches, then recombine rectangle and circle area calculations.

Refactor a dotnet example to curb a lava flow anti-pattern by removing deprecated functions, unused variables, and unreachable code, ending with a concise rectangle area calculation.

Design and refactor a guess game in C# from spaghetti antipattern to clean, efficient code, using a pseudo random number between 1 and 100, with user feedback and try tracking.

Refactor a two-player dice roll game in JavaScript from spaghetti code to modular functions, including roll die, update scores, determine winner, and display winner.

this lecture demonstrates turning a spaghetti antipattern pygame example into a modular, object oriented game by introducing a player class, handling input, updating state, and drawing the screen.

Demonstrate the primitive obsession antipattern in a C# list of people with dictionary addresses, refactor to an Address class, then cover average salary and filtering by job and city.

Demonstrate the primitive obsession antipattern in a Python script, show how to replace primitive data types with address and person classes, and sketch a refactor to structured objects.

Refactor a JavaScript example to replace primitive obsession with well-defined address and person classes, showcasing structured data, maintainability, and clearer salary calculations.

Explore the big ball of mud, its causes and consequences, and apply refactoring, modularization, improved documentation and communication, and design patterns to keep code clean and maintainable.

Build a treasure game in basic HTML and antipattern JavaScript, using a 2D map and a move-player function for north, south, east, and west, with monsters and treasure.

Refactors an ordering system by separating concerns into order, discount calculator, shipping service, and payment processor, improving testability and single-responsibility compliance.

Refactor the cave game into an adventure class with defined methods, replacing antipatterns, standardizing input handling, and creating maintainable paths suitable for unit tests.