Gradle Application Plugin

External

• https://docs.gradle.org/4.7/userguide/application_plugin.html

Internal

• Gradle Concepts
• Gradle Distribution Plugin

Overview

The application plugin facilitates creating an executable JVM application. It bundles all application JARS, transitive dependencies and operating system specific scripts into a TAR or ZIP file, and it also generates the bash and Windows wrapper scripts to run the application with. The plugin also allows executing the application from the project's work area with the "run" task.

Typical Setup

This setup describes configuration of a multi-project build, whose sub-project create various components of the application and the top level project bundles all those in a distributable artifact. The dependencies between the sub-projects must be configured in the corresponding build.gradle files. To build the application artifact, we assume that there's a sub-project that contains the "main()" static method that triggers the execution, that method exists in "io.example.Main" class, and the sub-project in question is named "main".

As such, the top-level project build.gradle should contain the following relevant configuration:

...

apply plugin: 'application'

mainClassName = "io.example.Main"

dependencies {

    ...

    implementation project(':main')
}

Provided that the rest of the dependencies between sub-projects are correctly declared in the corresponding build.gradle files, the execution of

gradle distZip

will compile everything and will create a ./build/distributions/<rootProject.name>.zip file. The file includes the sub-project artifacts, their transitive dependencies, and wrapper scripts for bash and Windows.

For more details about rootProject.name, see:

rootProject

Properties

mainClassName

mainClassName = 'greeter.Greeter'

Executing the Application from Project Work Area

gradle run

However, if the application requires command line parameters, they are not propagated. TODO: find a solution. A temporary solution is to unzip the application ZIP in a temp directory and then repeatedly overwrite the relevant JARs

Wrapper Script Customization

TODO: next time when I am here.