In 2009 I started to write small blog posts about Groovy at Messages from mrhaki. The posts contained code samples of cool Groovy features I just didn't want to forget. The blog posts turned out to be a useful resource for people learning and using Groovy in their every day programming.

The Groovy Goodness Notebook contains the blog posts about Groovy previously mentioned on my blog. The posts have been edited slightly so they can be used for the book. The book gives a broad overview of all the great features we can find in the Groovy language.

Updated on October 1, 2021 to include the following new subjects:

• Direct Field Access In (Super) Classes
• Identity Closure
• Groovy Goodness Notebook Is Updated
• Uncapitalize Strings
• Creating Root JSON Array With JsonBuilder
• Using The Call Operator ()
• Redirecting Print Methods In Scripts
• Download Grab Dependencies In IntelliJ IDEA
• Make Sure Closeable Objects Are Closed Using withCloseable Method
• Add Map Constructor With Annotation
• Base64 URL and Filename Safe Encoding
• Calculate MD5 And SHA Hash Values
• Creating Extra Method Supporting Named Arguments Using @NamedVariant Annotation
• Customizing JSON Output
• Easy Object Creation With Tap Method
• Getting All Init And Tail Values Recursively 
• Implement Interface And Abstract Methods Automatically
• Intersect Collections With Custom Comparator
• Java 8 Stream Enhancements
• Preorder And Postorder Tree Traversal
• Remove Last Item From List Using RemoveLast Method (And Pop/Push Methods Reimplemented)
• Truncate And Round BigDecimal Values
• Tuples With Up To 9 Items
• Unmodifiable Collections
• Use Optional In Conditional Context
• Use Range By Method To Set Steps Between Numbers
• Using String Values In Ranges
• Where Is My Class?
• Use Expanded Variables in SQL GString Query
• Transform Elements While Flattening
• Calculate Average For Collection
• Check Item Is Not In A Collection With !in
• Create YAML With YamlBuilder
• The Elvis Assignment Operator
• Lambda Default Parameter Value
• Parse YAML With YamlSlurper
• Shuffle List or Array
• Check Object Instances Are The Same With === Operator
• Getting Parts Of A String Enclosed By Strings
• Safe Index Based Access For Lists, Arrays and Maps
• Taking Or Dropping Number Of Characters From A String
• Using !instanceof Operator

The book categorizes the posts into the following sections:

• Syntax
• Operators
• Numbers
• Strings
• Regular Expressions
• Dates
• Lists, Ranges and Arrays
• Maps
• Closures
• SQL
• Files, Reades, Writers and URls
• XML and JSON
• AST transformations
• Metaprogramming
• DSL and Builder Support
• Scripts
• Testing
• Miscellaneous

In 2009 I started to write small blog posts about Gradle at Messages from mrhaki. The posts contained code samples of cool Gradle features I just didn't want to forget. The blog posts turned out to be a useful resource for people learning and using Groovy in their every day programming.

The Gradle Goodness Notebook contains the blog posts about Gradle previously mentioned on my blog. The posts have been edited slightly so they can be used for the book. The book gives a broad overview of all the great features we can find in the Gradle build tool.

Latest update on October 6, 2021 with the following blog posts:

• Add But Do Not Apply Plugin Using Plugins Block
• Adding Task With Rule Based Model Configuration
• Creation Rules For Rule Based Model Configuration Using Model DSL
• Custom Plugin Repositories With Plugins DSL
• Delegate Build And Run Actions To Gradle In IntelliJ IDEA
• Get Model Report In Short Format
• Getting Project Information Into Rule Based Model Configuration
• Replacing << Operator For Tasks
• Set Default Values With Rule Based Model Configuration
• Show Hidden Model Objects
• Validate Model In Rule Based Model Configuration
• Passing Environment Variable Via Delegate Run Action In IntelliJ IDEA
• Run Task Ignoring Up-to-date Checks
• Check Operating System In Build Scripts
• Skip Task When Input Empty Using @SkipWhenEmpty Annotation
• Create Shortcut Key To Refresh Gradle Projects In IntellIJ IDEA
• Change Local Build Cache Directory
• Enable Build Cache For All Builds
• Using Incremental Task Action
• Command Line Options For Custom Tasks
• Enable Task Based On Offline Command Line Argument
• Generate Javadoc In HTML5
• Rerun Incremental Tasks At Specific Intervals
• Only Show All Tasks In A Group
• Manage Dependency Versions With Dependency Constraints
• Use bill of materials (BOM) As Dependency Constraints
• Stop Build After One Failing Test
• Replace Files In Archives
• Setting Plugin Version From Property In Plugins Section
• Shared Configuration With Conventions Plugin
• Add Support For "Scratch" Files To Java Project
• Create Properties File With WriteProperties Task
• Enabling Preview Features For Java

The book contains the following sections:

• Tasks
• Configuration
• Command line
• Java and Groovy
• Miscellaneous