Kotlin® Notes for Professionals book

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Chapter 1: Getting started with Kotlin
	Section 1.1: Hello World
	Section 1.2: Hello World using a Companion Object
	Section 1.3: Hello World using an Object Declaration
	Section 1.4: Main methods using varargs
	Section 1.5: Compile and Run Kotlin Code in Command Line
	Section 1.6: Reading input from Command Line
Chapter 2: Basics of Kotlin
	Section 2.1: Basic examples
Chapter 3: Strings
	Section 3.1: String Equality
	Section 3.2: String Literals
	Section 3.3: Elements of String
	Section 3.4: String Templates
Chapter 4: Arrays
	Section 4.1: Generic Arrays
	Section 4.2: Arrays of Primitives
	Section 4.3: Create an array
	Section 4.4: Create an array using a closure
	Section 4.5: Create an uninitialized array
	Section 4.6: Extensions
	Section 4.7: Iterate Array
Chapter 5: Collections
	Section 5.1: Using list
	Section 5.2: Using map
	Section 5.3: Using set
Chapter 6: Enum
	Section 6.1: Initialization
	Section 6.2: Functions and Properties in enums
	Section 6.3: Simple enum
	Section 6.4: Mutability
Chapter 7: Functions
	Section 7.1: Function References
	Section 7.2: Basic Functions
	Section 7.3: Inline Functions
	Section 7.4: Lambda Functions
	Section 7.5: Operator functions
	Section 7.6: Functions Taking Other Functions
	Section 7.7: Shorthand Functions
Chapter 8: Vararg Parameters in Functions
	Section 8.1: Basics: Using the vararg keyword
	Section 8.2: Spread Operator: Passing arrays into vararg functions
Chapter 9: Conditional Statements
	Section 9.1: When-statement argument matching
	Section 9.2: When-statement as expression
	Section 9.3: Standard if-statement
	Section 9.4: If-statement as an expression
	Section 9.5: When-statement instead of if-else-if chains
	Section 9.6: When-statement with enums
Chapter 10: Loops in Kotlin
	Section 10.1: Looping over iterables
	Section 10.2: Repeat an action x times
	Section 10.3: Break and continue
	Section 10.4: Iterating over a Map in kotlin
	Section 10.5: Recursion
	Section 10.6: While Loops
	Section 10.7: Functional constructs for iteration
Chapter 11: Ranges
	Section 11.1: Integral Type Ranges
	Section 11.2: downTo() function
	Section 11.3: step() function
	Section 11.4: until function
Chapter 12: Regex
	Section 12.1: Idioms for Regex Matching in When Expression
	Section 12.2: Introduction to regular expressions in Kotlin
Chapter 13: Basic Lambdas
	Section 13.1: Lambda as parameter to filter function
	Section 13.2: Lambda for benchmarking a function call
	Section 13.3: Lambda passed as a variable
Chapter 14: Null Safety
	Section 14.1: Smart casts
	Section 14.2: Assertion
	Section 14.3: Eliminate nulls from an Iterable and array
	Section 14.4: Null Coalescing / Elvis Operator
	Section 14.5: Nullable and Non-Nullable types
	Section 14.6: Elvis Operator (?:)
	Section 14.7: Safe call operator
Chapter 15: Class Delegation
	Section 15.1: Delegate a method to another class
Chapter 16: Class Inheritance
	Section 16.1: Basics: the \'open\' keyword
	Section 16.2: Inheriting fields from a class
	Section 16.3: Inheriting methods from a class
	Section 16.4: Overriding properties and methods
Chapter 17: Visibility Modifiers
	Section 17.1: Code Sample
Chapter 18: Generics
	Section 18.1: Declaration-site variance
	Section 18.2: Use-site variance
Chapter 19: Interfaces
	Section 19.1: Interface with default implementations
	Section 19.2: Properties in Interfaces
	Section 19.3: super keyword
	Section 19.4: Basic Interface
	Section 19.5: Conflicts when Implementing Multiple Interfaces with Default Implementations
Chapter 20: Singleton objects
	Section 20.1: Use as replacement of static methods/fields of java
	Section 20.2: Use as a singleton
Chapter 21: coroutines
	Section 21.1: Simple coroutine which delay\'s 1 second but not blocks
Chapter 22: Annotations
	Section 22.1: Meta-annotations
	Section 22.2: Declaring an annotation
Chapter 23: Type aliases
	Section 23.1: Function type
	Section 23.2: Generic type
Chapter 24: Type-Safe Builders
	Section 24.1: Type-safe tree structure builder
Chapter 25: Delegated properties
	Section 25.1: Observable properties
	Section 25.2: Custom delegation
	Section 25.3: Lazy initialization
	Section 25.4: Map-backed properties
	Section 25.5: Delegate Can be used as a layer to reduce boilerplate
Chapter 26: Reflection
	Section 26.1: Referencing a class
	Section 26.2: Inter-operating with Java reflection
	Section 26.3: Referencing a function
	Section 26.4: Getting values of all properties of a class
	Section 26.5: Setting values of all properties of a class
Chapter 27: Extension Methods
	Section 27.1: Potential Pitfall: Extensions are Resolved Statically
	Section 27.2: Top-Level Extensions
	Section 27.3: Lazy extension property workaround
	Section 27.4: Sample extending Java 7+ Path class
	Section 27.5: Sample extending long to render a human readable string
	Section 27.6: Sample extending Java 8 Temporal classes to render an ISO formatted string
	Section 27.7: Using extension functions to improve readability
	Section 27.8: Extension functions to Companion Objects (appearance of Static functions)
	Section 27.9: Extensions for easier reference View from code
Chapter 28: DSL Building
	Section 28.1: Infix approach to build DSL
	Section 28.2: Using operators with lambdas
	Section 28.3: Overriding invoke method to build DSL
	Section 28.4: Using extensions with lambdas
Chapter 29: Idioms
	Section 29.1: Serializable and serialVersionUid in Kotlin
	Section 29.2: Delegate to a class without providing it in the public constructor
	Section 29.3: Use let or also to simplify working with nullable objects
	Section 29.4: Use apply to initialize objects or to achieve method chaining
	Section 29.5: Fluent methods in Kotlin
	Section 29.6: Filtering a list
	Section 29.7: Creating DTOs (POJOs/POCOs)
Chapter 30: RecyclerView in Kotlin
	Section 30.1: Main class and Adapter
Chapter 31: logging in kotlin
	Section 31.1: kotlin.logging
Chapter 32: Exceptions
	Section 32.1: Catching exception with try-catch-finally
Chapter 33: JUnit
	Section 33.1: Rules
Chapter 34: Kotlin Android Extensions
	Section 34.1: Using Views
	Section 34.2: Configuration
	Section 34.3: Painful listener for getting notice, when the view is completely drawn now is so simple and awesome with Kotlin\'s extension
	Section 34.4: Product flavors
Chapter 35: Kotlin for Java Developers
	Section 35.1: Declaring Variables
	Section 35.2: Quick Facts
	Section 35.3: Equality & Identity
	Section 35.4: IF, TRY and others are expressions, not statements
Chapter 36: Java 8 Stream Equivalents
	Section 36.1: Accumulate names in a List
	Section 36.2: Collect example #5 - find people of legal age, output formatted string
	Section 36.3: Collect example #6 - group people by age, print age and names together
	Section 36.4: Dierent Kinds of Streams #7 - lazily iterate Doubles, map to Int, map to String, print each
	Section 36.5: Counting items in a list after filter is applied
	Section 36.6: Convert elements to strings and concatenate them, separated by commas
	Section 36.7: Compute sum of salaries of employee
	Section 36.8: Group employees by department
	Section 36.9: Compute sum of salaries by department
	Section 36.10: Partition students into passing and failing
	Section 36.11: Names of male members
	Section 36.12: Group names of members in roster by gender
	Section 36.13: Filter a list to another list
	Section 36.14: Finding shortest string a list
	Section 36.15: Dierent Kinds of Streams #2 - lazily using first item if exists
	Section 36.16: Dierent Kinds of Streams #3 - iterate a range of Integers
	Section 36.17: Dierent Kinds of Streams #4 - iterate an array, map the values, calculate the average
	Section 36.18: Dierent Kinds of Streams #5 - lazily iterate a list of strings, map the values, convert to Int, find max
	Section 36.19: Dierent Kinds of Streams #6 - lazily iterate a stream of Ints, map the values, print results
	Section 36.20: How streams work - filter, upper case, then sort a list
	Section 36.21: Dierent Kinds of Streams #1 - eager using first item if it exists
	Section 36.22: Collect example #7a - Map names, join together with delimiter
	Section 36.23: Collect example #7b - Collect with SummarizingInt
Chapter 37: Kotlin Caveats
	Section 37.1: Calling a toString() on a nullable type
Appendix A: Configuring Kotlin build
	Section A.1: Gradle configuration
	Section A.2: Using Android Studio
	Section A.3: Migrating from Gradle using Groovy script to Kotlin script
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