Refactoring by Leveraging Tests with Java & JUnit
This course focuses on the Refactor step in TDD, teaching developers to spot code smells and resolve them through refactoring. Using real-world examples, you'll identify common issues, apply refactoring techniques, and ensure functionality is preserved with existing tests.
Lessons and practices
Lesson 1: Eliminating Duplicated Code: Extract Functions and Refactor Magic Numbers
Refactor Duplicate Code in the Tests
Refactor Tests using Parameterization
Extract Function: calculateItemCost
Refactor Duplication between Calculate Functions
Refactor Magic Numbers to Constants
Lesson 2: Refactoring Long Methods with the Extract Method Technique
Extract User Validation
Extracting Validation into Validator Classes
Extract Data Normalization
Focusing on the Data Store
Lesson 3: Long Parameter List: Introduce Parameter Object
Streamline Parameters with a Parameter Object
Introduce a CoursePolicy Parameter Object
Re-order Parameters for Cohesion
Provide Defaults for Most Parameters
Lesson 4: Feature Envy: Move Method Refactoring with TDD
Extract StudentGrade Logic
Refactor: Move Method calculateFinalGrade
Getting rid of the GradeAnalyzer
Eliminate Feature Envy from the Student
Lesson 5: Large Classes: Extract Class Refactoring
Extract a CartItemCollection
Extract a PriceCalculator Class
Extract a DiscountCalculator Class
Write Tests for Extracted Classes
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