Gradle is a powerful build automation tool that is widely used in the Java ecosystem, and it integrates seamlessly with Groovy. In this module, we will explore the basics of Gradle, how to set up a Gradle project, and how to use Gradle to build and manage Groovy projects.

Gradle is an open-source build automation tool that is designed to be flexible and extensible. It uses a Groovy-based DSL (Domain-Specific Language) to define build scripts, making it a natural fit for Groovy developers.

• Declarative Builds: Use a Groovy-based DSL to define build logic.
• Incremental Builds: Only re-builds what has changed, improving build times.
• Dependency Management: Handles dependencies and transitive dependencies.
• Multi-Project Builds: Supports building multiple projects in a single build.
• Extensibility: Easily extendable with custom tasks and plugins.

• Java Development Kit (JDK) installed.
• Gradle installed (can be downloaded from gradle.org).

1. Download Gradle: Download the latest version of Gradle from the official website.
2. Extract Gradle: Extract the downloaded zip file to a directory of your choice.
3. Set Environment Variables:
   • Add the bin directory of the extracted Gradle to your PATH environment variable.
   • Verify the installation by running gradle -v in your terminal.

1. Create a New Directory:

   mkdir my-groovy-project
   cd my-groovy-project
   

2. Initialize a Gradle Project:

   gradle init --type groovy-library
   

3. Project Structure:

   my-groovy-project/
   ├── build.gradle
   ├── settings.gradle
   ├── src
   │   ├── main
   │   │   └── groovy
   │   └── test
   │       └── groovy
   

The build.gradle file is the heart of your Gradle project. It defines the build logic and dependencies.

• plugins: Applies the Groovy plugin to the project.
• repositories: Specifies where to find dependencies (e.g., Maven Central).
• dependencies: Lists the dependencies required for the project.

To build the project, run the following command in the project directory:

To run the project, you can create a custom task in build.gradle:

Then, run the task:

1. Create a Groovy Script: Create a file src/main/groovy/com/example/Main.groovy:

   package com.example
   
   class Main {
       static void main(String[] args) {
           println 'Hello, Gradle with Groovy!'
       }
   }
   

2. Build and Run:

   gradle build
   gradle run
   

1. Create a new directory for your project.
2. Initialize a new Gradle project with the Groovy plugin.
3. Add a simple Groovy script that prints "Hello, World!".
4. Build and run the project.

1. Create a new directory:

   mkdir hello-gradle
   cd hello-gradle
   

2. Initialize the project:

   gradle init --type groovy-library
   

3. Add the Groovy script:

   // src/main/groovy/com/example/HelloWorld.groovy
   package com.example
   
   class HelloWorld {
       static void main(String[] args) {
           println 'Hello, World!'
       }
   }
   

4. Build and run:

   gradle build
   gradle run
   

1. Add a new dependency to your build.gradle file.
2. Use the dependency in your Groovy script.

1. Add the dependency:

   dependencies {
       implementation 'org.apache.commons:commons-lang3:3.12.0'
   }
   

2. Use the dependency:

   // src/main/groovy/com/example/HelloWorld.groovy
   package com.example
   
   import org.apache.commons.lang3.StringUtils
   
   class HelloWorld {
       static void main(String[] args) {
           println StringUtils.capitalize('hello, world!')
       }
   }
   

3. Build and run:

   gradle build
   gradle run
   

In this module, we covered the basics of Gradle, including setting up a Gradle project, understanding the build.gradle file, and building and running a Groovy project with Gradle. We also provided practical examples and exercises to reinforce the concepts. Gradle is a powerful tool that can greatly enhance your productivity when working with Groovy projects. In the next module, we will explore the Spock Testing Framework, which is a popular testing framework for Groovy applications.