Gradle

Overview

Gradle is a build tool for Java.

Example Project

The following steps create a simple Java project that can be built using Gradle.

Install SDKMAN!.
Install Gradle by entering sdk install gradle 8.8
Create a directory for the project.

Create the file build.gradle, which uses Groovy, in the project directory containing the following:

plugins {
   id 'application'
   id 'java'
}

application {
   // applicationDefaultJvmArgs = ['-Dgreeting.language=en']
   mainClass = 'HelloWorld'
}

java {
   sourceCompatibility = JavaVersion.VERSION_18
}

repositories {
   mavenCentral()
}

dependencies {
   // Add dependencies here if needed
}

Inside the project directory, create the diretory src/main/java.

Create the file src/main/java/HelloWorld.java containing the following:

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

To build the project, enter gradle build

This creates the build subdirectory if it doesn’t exist and it writes all generated files inside that directory.
To run the project, enter gradle run

This will also build the project before running if it has not been built or if source files have been modified since the last build. So it is never necessary to run gradle build.
To delete all the generated files (the build directory), enter gradle clean.

Kotlin

The following file build.gradle.kts is nearly identical to the build.gradle file above, but it uses Kotlin instead of Groovy.

plugins {
    // The "java" and "application" plugins are special.
    // All other plugins must use the syntax `id("plugin.id")`.
    id 'application'
    id 'java'
}

application {
    applicationDefaultJvmArgs = ['-Dgreeting.language=en']
    mainClass = 'HelloWorld'
}

java {
    sourceCompatibility = JavaVersion.VERSION_18
}

repositories {
    mavenCentral()
}

dependencies {
    // Add dependencies here if needed
}