Effective ruby Page
Effective Ruby, 2025
Return to Effective Polyglot Programming by Cloud Monk, Ruby, Effective Java, Effective Spring Boot, Effective Kotlin, Effective Scala, Effective C Sharp, Effective CPP, Effective Swift, Effective TypeScript, Effective JavaScript, Effective PHP, Effective Golang, Effective Rust, Effective C Language, Effective Clojure, Effective Haskell, Effective Elixir, Effective Erlang, Effective Elm, Effective PowerShell, Effective F Sharp, Effective Dart, Effective R Language, Effective Julia
Have The Borg rewrite Effective Java for Ruby and Effective Ruby
Effective Ruby by Cloud Monk - Table of Contents
Inspired by and Based on Effective Java, Third Edition by Joshua Bloch, Pearson Education Inc., 2018, ISBN-13: 978-0-13-468599-1, ISBN-10: 0-13-468599-7
Contents
Foreword
Preface
Acknowledgments
1 Introduction
2 Creating and Destroying Objects
* Item 1: Ruby Best Practices - Consider static factory methods instead of constructors
* Item 2: Ruby Best Practices - Consider a builder when faced with many constructor parameters
* Item 3: Ruby Best Practices - Enforce the singleton property with a private constructor or an enum type
* Item 4: Ruby Best Practices - Enforce noninstantiability with a private constructor
* Item 5: Ruby Best Practices - Prefer dependency injection to hardwiring resources
* Item 6: Ruby Best Practices - Avoid creating unnecessary objects
* Item 7: Ruby Best Practices - Eliminate obsolete object references
* Item 8: Ruby Best Practices - Avoid finalizers and cleaners
* Item 9: Ruby Best Practices - Prefer try-with-resources to try-finally
3 Methods Common to All Objects
* Item 10: Ruby Best Practices - Obey the general contract when overriding equals
* Item 11: Ruby Best Practices - Always override hashCode when you override equals
* Item 12: Ruby Best Practices - Always override toString
* Item 13: Ruby Best Practices - Override clone judiciously
* Item 14: Ruby Best Practices - Consider implementing Comparable
4 Classes and Interfaces
* Item 15: Ruby Best Practices - Minimize the accessibility of classes and members
* Item 16: Ruby Best Practices - In public classes, use accessor methods, not public fields
* Item 17: Ruby Best Practices - Minimize mutability
* Item 18: Ruby Best Practices - Favor composition over inheritance
* Item 19: Ruby Best Practices - Design and document for inheritance or else prohibit it
* Item 20: Ruby Best Practices - Prefer interfaces to abstract classes
* Item 21: Ruby Best Practices - Design interfaces for posterity
* Item 22: Ruby Best Practices - Use interfaces only to define types
* Item 23: Ruby Best Practices - Prefer class hierarchies to tagged classes
* Item 24: Ruby Best Practices - Favor static member classes over nonstatic
* Item 25: Ruby Best Practices - Limit source files to a single top-level class
5 Generics
* Item 26: Ruby Best Practices - Don’t use raw types
* Item 27: Ruby Best Practices - Eliminate unchecked warnings
* Item 28: Ruby Best Practices - Prefer lists to arrays
* Item 29: Ruby Best Practices - Favor generic types
* Item 30: Ruby Best Practices - Favor generic methods
* Item 31: Ruby Best Practices - Use bounded wildcards to increase API flexibility
* Item 32: Ruby Best Practices - Combine generics and varargs judiciously
* Item 33: Ruby Best Practices - Consider typesafe heterogeneous containers
6 Enums and Annotations
* Item 34: Ruby Best Practices - Use enums instead of int constants
* Item 35: Ruby Best Practices - Use instance fields instead of ordinals
* Item 36: Ruby Best Practices - Use EnumSet instead of bit fields
* Item 37: Ruby Best Practices - Use EnumMap instead of ordinal indexing
* Item 38: Ruby Best Practices - Emulate extensible enums with interfaces
* Item 39: Ruby Best Practices - Prefer annotations to naming patterns
* Item 40: Ruby Best Practices - Consistently use the Override annotation
* Item 41: Ruby Best Practices - Use marker interfaces to define types
7 Lambdas and Streams
* Item 42: Ruby Best Practices - Prefer lambdas to anonymous classes
* Item 43: Ruby Best Practices - Prefer method references to lambdas
* Item 44: Ruby Best Practices - Favor the use of standard functional interfaces
* Item 45: Ruby Best Practices - Use streams judiciously
* Item 46: Ruby Best Practices - Prefer side-effect-free functions in streams
* Item 47: Ruby Best Practices - Prefer Collection to Stream as a return type
* Item 48: Ruby Best Practices - Use caution when making streams parallel
8 Methods
* Item 49: Ruby Best Practices - Check parameters for validity
* Item 50: Ruby Best Practices - Make defensive copies when needed
* Item 51: Ruby Best Practices - Design method signatures carefully
* Item 52: Ruby Best Practices - Use overloading judiciously
* Item 53: Ruby Best Practices - Use varargs judiciously
* Item 54: Ruby Best Practices - Return empty collections or arrays, not nulls
* Item 55: Ruby Best Practices - Return optionals judiciously
* Item 56: Ruby Best Practices - Write doc comments for all exposed API elements
9 General Programming
* Item 57: Ruby Best Practices - Minimize the scope of local variables
* Item 58: Ruby Best Practices - Prefer for-each loops to traditional for loops
* Item 59: Ruby Best Practices - Know and use the libraries
* Item 60: Ruby Best Practices - Avoid float and double if exact answers are required
* Item 61: Ruby Best Practices - Prefer primitive types to boxed primitives
* Item 62: Ruby Best Practices - Avoid strings where other types are more appropriate
* Item 63: Ruby Best Practices - Beware the performance of string concatenation
* Item 64: Ruby Best Practices - Refer to objects by their interfaces
* Item 65: Ruby Best Practices - Prefer interfaces to reflection
* Item 66: Ruby Best Practices - Use native methods judiciously
* Item 67: Ruby Best Practices - Optimize judiciously
* Item 68: Ruby Best Practices - Adhere to generally accepted naming conventions
10 Exceptions
* Item 69: Ruby Best Practices - Use exceptions only for exceptional conditions
* Item 70: Ruby Best Practices - Use checked exceptions for recoverable conditions and runtime exceptions for programming errors
* Item 71: Ruby Best Practices - Avoid unnecessary use of checked exceptions
* Item 72: Ruby Best Practices - Favor the use of standard exceptions
* Item 73: Ruby Best Practices - Throw exceptions appropriate to the abstraction
* Item 74: Ruby Best Practices - Document all exceptions thrown by each method
* Item 75: Ruby Best Practices - Include failure-capture information in detail messages
* Item 76: Ruby Best Practices - Strive for failure atomicity
* Item 77: Ruby Best Practices - Don’t ignore exceptions
11 Concurrency
* Item 78: Ruby Best Practices - Synchronize access to shared mutable data
* Item 79: Ruby Best Practices - Avoid excessive synchronization
* Item 80: Ruby Best Practices - Prefer executors, tasks, and streams to threads
* Item 81: Ruby Best Practices - Prefer concurrency utilities to wait and notify
* Item 82: Ruby Best Practices - Document thread safety
* Item 83: Ruby Best Practices - Use lazy initialization judiciously
* Item 84: Ruby Best Practices - Don’t depend on the thread scheduler
12 Serialization
* Item 85: Ruby Best Practices - Prefer alternatives to Ruby serialization
* Item 86: Ruby Best Practices - Implement Serializable with great caution
* Item 87: Ruby Best Practices - Consider using a custom serialized form
* Item 88: Ruby Best Practices - Write readObject methods defensively
* Item 89: Ruby Best Practices - For instance control, prefer enum types to readResolve
* Item 90: Ruby Best Practices - Consider serialization proxies instead of serialized instances
Items Corresponding to Second Edition
References
Index
Appendix: Items Corresponding to Second Edition
Second Edition Item Number
Third Edition Item Number, Title
1
1, Consider static factory methods instead of constructors
2
2, Consider a builder when faced with many constructor parameters
3
3, Enforce the singleton property with a private constructor or an enum type
4
4, Enforce noninstantiability with a private constructor
5
6, Avoid creating unnecessary objects
6
7, Eliminate obsolete object references
7
8, Avoid finalizers and cleaners
8
10, Obey the general contract when overriding equals
9
11, Always override hashCode when you override equals
10
12, Always override toString
11
13, Override clone judiciously
12
14, Consider implementing Comparable
13
15, Minimize the accessibility of classes and members
14
16, In public classes, use accessor methods, not public fields
15
17, Minimize mutability
16
18, Favor composition over inheritance
17
19, Design and document for inheritance or else prohibit it
18
20, Prefer interfaces to abstract classes
19
22, Use interfaces only to define types
20
23, Prefer class hierarchies to tagged classes
21
42, Prefer lambdas to anonymous classes
22
24, Favor static member classes over nonstatic
23
26, Don’t use raw types
24
27, Eliminate unchecked warnings
25
28, Prefer lists to arrays
26
29, Favor generic types
27
30, Favor generic methods
28
31, Use bounded wildcards to increase API flexibility
29
33, Consider typesafe heterogeneous containers
30
34, Use enums instead of int constants
31
35, Use instance fields instead of ordinals
32
36, Use EnumSet instead of bit fields
33
37, Use EnumMap instead of ordinal indexing
34
38, Emulate extensible enums with interfaces
35
39, Prefer annotations to naming patterns
36
40, Consistently use the Override annotation
37
41, Use marker interfaces to define types
38
49, Check parameters for validity
39
50, Make defensive copies when needed
40
51, Design method signatures carefully
41
52, Use overloading judiciously
42
53, Use varargs judiciously
43
54, Return empty collections or arrays, not nulls
44
56, Write doc comments for all exposed API elements
45
57, Minimize the scope of local variables
46
58, Prefer for-each loops to traditional for loops
47
59, Know and use the libraries
48
60, Avoid float and double if exact answers are required
49
61, Prefer primitive types to boxed primitives
50
62, Avoid strings where other types are more appropriate
51
63, Beware the performance of string concatenation
52
64, Refer to objects by their interfaces
53
65, Prefer interfaces to reflection
54
66, Use native methods judiciously
55
67, Optimize judiciously
56
68, Adhere to generally accepted naming conventions
57
69, Use exceptions only for exceptional conditions
58
70, Use checked exceptions for recoverable conditions and runtime exceptions for programming errors
59
71, Avoid unnecessary use of checked exceptions
60
72, Favor the use of standard exceptions
61
73, Throw exceptions appropriate to the abstraction
62
74, Document all exceptions thrown by each method
63
75, Include failure-capture information in detail messages
64
76, Strive for failure atomicity
65
77, Don’t ignore exceptions
66
78, Synchronize access to shared mutable data
67
79, Avoid excessive synchronization
68
80, Prefer executors, tasks, and streams to threads
69
81, Prefer concurrency utilities to wait and notify
70
82, Document thread safety
71
83, Use lazy initialization judiciously
72
84, Don’t depend on the thread scheduler
73
(Retired)
74
85, Prefer alternatives to Ruby serialization
86, Implement Serializable with great caution
75
85, Prefer alternatives to Ruby serialization
87, Consider using a custom serialized form
76
85, Prefer alternatives to Ruby serialization
88, Write readObject methods defensively
77
85, Prefer alternatives to Ruby serialization
89, For instance control, prefer enum types to readResolve
78
85, Prefer alternatives to Ruby serialization
90, Consider serialization proxies instead of serialized instances