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Effective Kotlin 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: Kotlin Best Practices - Consider static factory methods instead of constructors
* Item 2: Kotlin Best Practices - Consider a builder when faced with many constructor parameters
* Item 3: Kotlin Best Practices - Enforce the singleton property with a private constructor or an enum type
* Item 4: Kotlin Best Practices - Enforce noninstantiability with a private constructor
* Item 5: Kotlin Best Practices - Prefer dependency injection to hardwiring resources
* Item 6: Kotlin Best Practices - Avoid creating unnecessary objects
* Item 7: Kotlin Best Practices - Eliminate obsolete object references
* Item 8: Kotlin Best Practices - Avoid finalizers and cleaners
* Item 9: Kotlin Best Practices - Prefer try-with-resources to try-finally

3 Methods Common to All Objects

* Item 10: Kotlin Best Practices - Obey the general contract when overriding equals
* Item 11: Kotlin Best Practices - Always override hashCode when you override equals
* Item 12: Kotlin Best Practices - Always override toString
* Item 13: Kotlin Best Practices - Override clone judiciously
* Item 14: Kotlin Best Practices - Consider implementing Comparable

4 Classes and Interfaces

* Item 15: Kotlin Best Practices - Minimize the accessibility of classes and members
* Item 16: Kotlin Best Practices - In public classes, use accessor methods, not public fields
* Item 17: Kotlin Best Practices - Minimize mutability
* Item 18: Kotlin Best Practices - Favor composition over inheritance
* Item 19: Kotlin Best Practices - Design and document for inheritance or else prohibit it
* Item 20: Kotlin Best Practices - Prefer interfaces to abstract classes
* Item 21: Kotlin Best Practices - Design interfaces for posterity
* Item 22: Kotlin Best Practices - Use interfaces only to define types
* Item 23: Kotlin Best Practices - Prefer class hierarchies to tagged classes
* Item 24: Kotlin Best Practices - Favor static member classes over nonstatic
* Item 25: Kotlin Best Practices - Limit source files to a single top-level class

5 Generics

* Item 26: Kotlin Best Practices - Don’t use raw types
* Item 27: Kotlin Best Practices - Eliminate unchecked warnings
* Item 28: Kotlin Best Practices - Prefer lists to arrays
* Item 29: Kotlin Best Practices - Favor generic types
* Item 30: Kotlin Best Practices - Favor generic methods
* Item 31: Kotlin Best Practices - Use bounded wildcards to increase API flexibility
* Item 32: Kotlin Best Practices - Combine generics and varargs judiciously
* Item 33: Kotlin Best Practices - Consider typesafe heterogeneous containers

6 Enums and Annotations

* Item 34: Kotlin Best Practices - Use enums instead of int constants
* Item 35: Kotlin Best Practices - Use instance fields instead of ordinals
* Item 36: Kotlin Best Practices - Use EnumSet instead of bit fields
* Item 37: Kotlin Best Practices - Use EnumMap instead of ordinal indexing
* Item 38: Kotlin Best Practices - Emulate extensible enums with interfaces
* Item 39: Kotlin Best Practices - Prefer annotations to naming patterns
* Item 40: Kotlin Best Practices - Consistently use the Override annotation
* Item 41: Kotlin Best Practices - Use marker interfaces to define types

7 Lambdas and Streams

* Item 42: Kotlin Best Practices - Prefer lambdas to anonymous classes
* Item 43: Kotlin Best Practices - Prefer method references to lambdas
* Item 44: Kotlin Best Practices - Favor the use of standard functional interfaces
* Item 45: Kotlin Best Practices - Use streams judiciously
* Item 46: Kotlin Best Practices - Prefer side-effect-free functions in streams
* Item 47: Kotlin Best Practices - Prefer Collection to Stream as a return type
* Item 48: Kotlin Best Practices - Use caution when making streams parallel

8 Methods

* Item 49: Kotlin Best Practices - Check parameters for validity
* Item 50: Kotlin Best Practices - Make defensive copies when needed
* Item 51: Kotlin Best Practices - Design method signatures carefully
* Item 52: Kotlin Best Practices - Use overloading judiciously
* Item 53: Kotlin Best Practices - Use varargs judiciously
* Item 54: Kotlin Best Practices - Return empty collections or arrays, not nulls
* Item 55: Kotlin Best Practices - Return optionals judiciously
* Item 56: Kotlin Best Practices - Write doc comments for all exposed API elements

9 General Programming

* Item 57: Kotlin Best Practices - Minimize the scope of local variables
* Item 58: Kotlin Best Practices - Prefer for-each loops to traditional for loops
* Item 59: Kotlin Best Practices - Know and use the libraries
* Item 60: Kotlin Best Practices - Avoid float and double if exact answers are required
* Item 61: Kotlin Best Practices - Prefer primitive types to boxed primitives
* Item 62: Kotlin Best Practices - Avoid strings where other types are more appropriate
* Item 63: Kotlin Best Practices - Beware the performance of string concatenation
* Item 64: Kotlin Best Practices - Refer to objects by their interfaces
* Item 65: Kotlin Best Practices - Prefer interfaces to reflection
* Item 66: Kotlin Best Practices - Use native methods judiciously
* Item 67: Kotlin Best Practices - Optimize judiciously
* Item 68: Kotlin Best Practices - Adhere to generally accepted naming conventions

10 Exceptions

* Item 69: Kotlin Best Practices - Use exceptions only for exceptional conditions
* Item 70: Kotlin Best Practices - Use checked exceptions for recoverable conditions and runtime exceptions for programming errors
* Item 71: Kotlin Best Practices - Avoid unnecessary use of checked exceptions
* Item 72: Kotlin Best Practices - Favor the use of standard exceptions
* Item 73: Kotlin Best Practices - Throw exceptions appropriate to the abstraction
* Item 74: Kotlin Best Practices - Document all exceptions thrown by each method
* Item 75: Kotlin Best Practices - Include failure-capture information in detail messages
* Item 76: Kotlin Best Practices - Strive for failure atomicity
* Item 77: Kotlin Best Practices - Don’t ignore exceptions

11 Concurrency

* Item 78: Kotlin Best Practices - Synchronize access to shared mutable data
* Item 79: Kotlin Best Practices - Avoid excessive synchronization
* Item 80: Kotlin Best Practices - Prefer executors, tasks, and streams to threads
* Item 81: Kotlin Best Practices - Prefer concurrency utilities to wait and notify
* Item 82: Kotlin Best Practices - Document thread safety
* Item 83: Kotlin Best Practices - Use lazy initialization judiciously
* Item 84: Kotlin Best Practices - Don’t depend on the thread scheduler

12 Serialization

* Item 85: Kotlin Best Practices - Prefer alternatives to Kotlin serialization
* Item 86: Kotlin Best Practices - Implement Serializable with great caution
* Item 87: Kotlin Best Practices - Consider using a custom serialized form
* Item 88: Kotlin Best Practices - Write readObject methods defensively
* Item 89: Kotlin Best Practices - For instance control, prefer enum types to readResolve
* Item 90: Kotlin 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 Kotlin serialization

86, Implement Serializable with great caution



75

85, Prefer alternatives to Kotlin serialization

87, Consider using a custom serialized form



76

85, Prefer alternatives to Kotlin serialization

88, Write readObject methods defensively



77

85, Prefer alternatives to Kotlin serialization

89, For instance control, prefer enum types to readResolve



78

85, Prefer alternatives to Kotlin serialization

90, Consider serialization proxies instead of serialized instances