Contents
Cover Page
About This E-Book
Front End Paper
Title Page
Copyright Page
Dedication Page
Contents
Foreword to the First Edition
Preface
What Is Refactoring?
What’s in This Book?
Who Should Read This Book?
Building on a Foundation Laid by Others
Acknowledgments
Chapter 1 Refactoring: A First Example
The Starting Point
Comments on the Starting Program
The First Step in Refactoring
Decomposing the statement Function
Status: Lots of Nested Functions
Splitting the Phases of Calculation and Formatting
Status: Separated into Two Files (and Phases)
Reorganizing the Calculations by Type
Status: Creating the Data with the Polymorphic Calculator
Final Thoughts
Chapter 2 Principles in Refactoring
Defining Refactoring
The Two Hats
Why Should We Refactor?
When Should We Refactor?
Problems with Refactoring
Refactoring, Architecture, and Yagni
Refactoring and the Wider Software Development Process
Refactoring and Performance
Where Did Refactoring Come From?
Automated Refactorings
Going Further
Chapter 3 Bad Smells in Code
Mysterious Name
Duplicated Code
Long Function
Long Parameter List
Global Data
Mutable Data
Divergent Change
Shotgun Surgery
Feature Envy
Data Clumps
Primitive Obsession
Repeated Switches
Loops
Lazy Element
Speculative Generality
Temporary Field
Message Chains
Middle Man
Insider Trading
Large Class
Alternative Classes with Different Interfaces
Data Class
Refused Bequest
Comments
Chapter 4 Building Tests
The Value of Self-Testing Code
Sample Code to Test
A First Test
Add Another Test
Modifying the Fixture
Probing the Boundaries
Much More Than This
Chapter 5 Introducing the Catalog
Format of the Refactorings
The Choice of Refactorings
Chapter 6 A First Set of Refactorings
Extract Function
Inline Function
Extract Variable
Inline Variable
Change Function Declaration
Encapsulate Variable
Rename Variable
Introduce Parameter Object
Combine Functions into Class
Combine Functions into Transform
Split Phase
Chapter 7 Encapsulation
Encapsulate Record
Encapsulate Collection
Replace Primitive with Object
Replace Temp with Query
Extract Class
Inline Class
Hide Delegate
Remove Middle Man
Substitute Algorithm
Chapter 8 Moving Features
Move Function
Move Field
Move Statements into Function
Move Statements to Callers
Replace Inline Code with Function Call
Slide Statements
Split Loop
Replace Loop with Pipeline
Remove Dead Code
Chapter 9 Organizing Data
Split Variable
Rename Field
Replace Derived Variable with Query
Change Reference to Value
Change Value to Reference
Chapter 10 Simplifying Conditional Logic
Decompose Conditional
Consolidate Conditional Expression
Replace Nested Conditional with Guard Clauses
Replace Conditional with Polymorphism
Introduce Special Case
Introduce Assertion
Chapter 11 Refactoring APIs
Separate Query from Modifier
Parameterize Function
Remove Flag Argument
Preserve Whole Object
Replace Parameter with Query
Replace Query with Parameter
Remove Setting Method
Replace Constructor with Factory Function
Replace Function with Command
Replace Command with Function
Chapter 12 Dealing with Inheritance
Pull Up Method
Pull Up Field
Pull Up Constructor Body
Push Down Method
Push Down Field
Replace Type Code with Subclasses
Remove Subclass
Extract Superclass
Collapse Hierarchy
Replace Subclass with Delegate
Replace Superclass with Delegate
Bibliography
Index
Back End Paper
Code Snippets
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