Groovy Study Notes

Building a Gradle Plugin in Groovy

A hands-on guide to writing, structuring, and publishing a custom Gradle plugin using Groovy, from the Plugin interface to the Gradle Plugin Portal.

Classes and Objects in Groovy

Learn how Groovy simplifies Java's class syntax with automatic property generation, flexible map-based constructors, and value-based equality, while still comp…

Closures in Groovy

How Groovy's first-class Closure type captures its defining scope, and how owner, delegate, and resolveStrategy power Groovy's DSL syntax.

Dynamic Method Dispatch

How Groovy resolves which method implementation to invoke at runtime based on actual argument types, and how this differs from Java's static dispatch.

Error Handling in Groovy

How Groovy handles exceptions, including its unchecked-exceptions model, try/catch/finally, multi-catch, custom exceptions, and null-safe operators that reduce…

Expando and MetaClass

How Groovy's Expando class and ExpandoMetaClass let you add properties and methods to objects dynamically at runtime, even to existing Java classes.

Groovy and Annotations

Understand how Groovy's AST transformation annotations like @Canonical, @Immutable, and @CompileStatic generate real code at compile time, and how to build you…

Groovy and Gradle

Learn how Gradle uses Groovy as its build-script DSL, covering tasks, dependencies, plugins, and multi-project builds.

Groovy and Grails Basics

An introduction to Grails, the convention-over-configuration web framework built on Groovy and Spring Boot, covering its MVC structure, GORM, and core project…

Groovy and Jenkins Pipelines

Understand how Jenkins Pipeline uses Groovy for both Declarative and Scripted syntax, including shared libraries and CPS constraints.

Groovy and Testing with Spock

Learn how the Spock Framework uses Groovy's syntax to write expressive, structured tests with given-when-then blocks, data tables, and built-in mocking.

Groovy Best Practices

Practical, idiomatic guidelines for writing clean, safe, and maintainable Groovy code in real-world projects.

Groovy Collections

How Groovy's native list and map literals, GDK methods like collect/findAll/inject/groupBy, ranges, and the spread operator make collection processing concise.

Groovy DSLs Explained

How Groovy's syntactic flexibility — optional parentheses, closures, and builders — enables readable internal domain-specific languages like Gradle and Jenkins…

Groovy Interview Questions

Commonly asked Groovy interview questions and the reasoning behind good answers, covering core syntax, closures, metaprogramming, and practical scenarios.

Groovy Quick Reference

A condensed cheat sheet of core Groovy syntax, operators, closures, and collection methods for quick lookup while coding.

Groovy Scripting for Automation

Learn how to use Groovy as a scripting language for file processing, running system commands, parsing command-line arguments, and building automation tools.

Groovy Syntax Basics

A tour of Groovy's core syntax conveniences - optional typing, GString interpolation, native collection literals, and closures - compared to plain Java.

Groovy vs Java

A side-by-side comparison of Groovy and Java covering syntax verbosity, static versus dynamic typing, performance, and when to reach for each language.

Groovy vs Java Comparison

A practical comparison of Groovy and Java covering syntax, typing, closures, and runtime performance to help you choose the right tool and write better JVM cod…

Installing Groovy

A practical walkthrough of installing Groovy via SDKMAN, manual download, or a package manager, and verifying the install with groovy, groovysh, and groovyCons…

Metaprogramming Basics

Explore Groovy's Meta Object Protocol — methodMissing, propertyMissing, ExpandoMetaClass, and Categories — for intercepting and extending behavior at runtime.

Operators and Truth in Groovy

Groovy's safe navigation, Elvis, and spaceship operators, operator overloading, and the rules of Groovy Truth for evaluating objects in boolean contexts.

Optional Typing in Groovy

How Groovy lets you mix def (dynamic) and explicit static types, and how @TypeChecked and @CompileStatic add compile-time safety and performance.