Groovy Programming Training Course

Introduction to Groovy

• Overview of Apache Groovy
• History and evolution of the language
• The relationship between Groovy and the Java Virtual Machine
• Groovy as both a scripting and full-fledged programming language
• Common use cases for Groovy
• Utilizing Groovy within Java-based projects
• Benefits of pairing Groovy with Java
• Preview of the sample application

Exploring Groovy Features

• Dynamic typing versus optional static typing
• Groovy scripting capabilities
• Concise syntax and language enhancements
• Closures and functional programming concepts
• Groovy collections and API improvements
• Operator overloading
• String interpolation
• Safe navigation and the Elvis operator
• Developing Domain-Specific Languages
• Meta-programming capabilities
• The Groovy Development Kit (GDK)

Configuring the Development Environment

• Installing and setting up Groovy
• Managing Groovy distributions
• Utilizing the command line interface
• Executing Groovy scripts
• Setting up an Integrated Development Environment (IDE)
• Initializing a new Groovy project
• Managing project dependencies
• Integrating Groovy with existing Java projects
• Configuring the environment for containerized development

Building Your First Groovy Application

• Creating a basic Groovy script
• Understanding the structure of Groovy scripts
• Running Groovy applications
• Using the println statement
• Working with variables
• Defining methods
• Adding comments and documentation
• Assembling a simple sample application
• Compiling Groovy code

Mastering Groovy Syntax

• Statements and expressions in Groovy
• Semicolons and optional syntax elements
• Variables and constants
• Dynamic typing versus explicit typing
• String literals and interpolation
• Single-line and multi-line strings
• Operators and complex expressions
• Groovy-specific operators and shortcuts
• Null handling strategies
• Safe navigation operators
• The Elvis operator
• Multiple assignment

Utilizing Groovy Data Types and Collections

• Primitive and object types
• Numbers and numeric operations
• Strings and character handling
• Boolean logic
• Date and time values
• Lists
• Maps
• Sets
• Ranges
• Iterating through collections
• Transforming collections
• Filtering and searching data
• Sorting and grouping data
• Groovy collection methods

Working with Groovy Closures

• Concept of closures
• Closure syntax
• Defining closure parameters
• Using implicit closure parameters
• Invoking closures
• Storing closures in variables
• Passing closures as arguments
• Returning closures from methods
• Using closures with collections
• Applying closures for filtering and transformation
• Scope rules and variable capture
• Leveraging closures for functional programming
• Practical patterns involving closures

Managing Program Flow with Control Structures

• Conditional logic
• Using if and else
• Nested conditional statements
• switch statements
• Loops and iteration
• for, while, and do-while loops
• Using ranges in loops
• Leveraging closures for iteration
• break and continue keywords
• Exception handling mechanisms
• try, catch, and finally blocks
• Throwing custom exceptions
• Groovy-specific control-flow features

Applying Object-Oriented Programming (OOP) in Your Application

• Defining Groovy classes
• Properties and fields
• Constructors
• Methods
• Encapsulation principles
• Inheritance
• Interfaces
• Abstract classes
• Polymorphism
• Method overriding
• Method overloading
• Groovy getters and setters
• Traits
• Enumerations (Enums)
• Creating domain models for the sample application

Runtime and Compile-Time MetaProgramming

• Introduction to Groovy meta-programming
• Dynamic method invocation
• Using Expando objects
• Manipulating methods and properties at runtime
• Categories and extension methods
• The MetaClass mechanism
• Dynamically adding methods
• Intercepting method calls
• Compile-time AST transformations
• Common Abstract Syntax Tree (AST) transformations
• Responsible use of meta-programming
• Practical examples of meta-programming

Working with Builders

• Introduction to the Builder pattern
• Purpose and utility of Groovy builders
• Creating hierarchical structures
• XML builders
• JSON builders
• Generating HTML and markup
• Configuring builder output
• Combining closures with builders
• Creating custom builders
• Applying builders in DSL development

Accessing Databases with Groovy

• Database connectivity fundamentals
• Connecting Groovy applications to databases
• JDBC and Groovy database APIs
• Configuring database connections
• Executing SQL queries
• Processing query results
• Performing Insert, Update, and Delete operations
• Using parameterized queries
• Managing transactions
• Handling database exceptions
• Utilizing Groovy SQL
• Implementing database functionality in the sample application

Interoperability: Calling Java from Groovy

• Groovy and Java interoperability
• Accessing Java classes from Groovy
• Invoking Java methods
• Working with Java libraries
• Using Java collections
• Handling Java exceptions
• Comparing Groovy and Java syntax
• Calling Groovy code from Java
• Mixing Groovy and Java source files
• Integrating Groovy into existing Java applications
• Best practices for interoperability

Integrating with REST Services and Applications

• Introduction to REST APIs
• HTTP concepts relevant to Groovy applications
• Sending HTTP requests
• Handling GET, POST, PUT, and DELETE methods
• Managing request parameters and headers
• Processing JSON responses
• Constructing JSON request bodies
• Implementing authentication
• Managing HTTP errors
• Consuming external REST services
• Incorporating REST functionality into the sample application

Utilizing the Groovy Development Kit (GDK)

• Introduction to the GDK
• Enhanced Java APIs
• String manipulation features
• Enhanced collection utilities
• File and directory operations
• Reading and writing files
• Working with streams
• Processing XML
• Processing JSON
• Handling dates and times
• Utility methods and convenience APIs
• Selecting appropriate GDK features

Unit Testing Groovy Applications

• Introduction to testing Groovy applications
• Test-driven development (TDD) concepts
• Writing unit tests
• Using testing frameworks
• Structuring test classes
• Writing assertions
• Testing classes and methods
• Testing closures
• Testing exception handling
• Mocking dependencies
• Data-driven testing techniques
• Testing database-related functionality
• Testing REST integrations
• Executing and analyzing test results

Troubleshooting and Debugging

• Diagnosing Groovy syntax errors
• Debugging runtime errors
• Addressing compilation issues
• Troubleshooting Java interoperability problems
• Debugging closures and collection operations
• Investigating database connectivity issues
• Troubleshooting REST API integrations
• Debugging meta-programming behavior
• Using logging and diagnostic tools
• Practical troubleshooting exercises

Summary and Conclusion

• Recap of Groovy language fundamentals
• Review of syntax, data types, and collections
• Review of closures and functional programming
• Review of object-oriented programming concepts
• Review of meta-programming and builders
• Review of database and REST integration
• Review of Groovy and Java interoperability
• Review of GDK capabilities
• Review of testing best practices
• Best practices for Groovy application development
• Final hands-on exercise
• Q&A session