maven-springboot-electron

Maven + Springboot + Electron (+ OpenJDK)

This project is a starting point to wrap any Java web application (f.e. using Springboot) with electron as a native executable. For the build process, only maven is being used. This project contains all the necessary configuration and some placeholder files to get you started.

This project was inspired a lot by electron-java-app, but it has some key differences:

• Instead of Gradle only Maven is being used (of course also Node but indirectly)
• When building the Electron application an OpenJDK will be included to start the Java web application

Proof of concept

The purpose of this project was sole of personal interest to show that this concept (Electron -> shipped JDK -> Java Web Application as Jar) is possible. Before taking it into production, you should check your requirements carefully. On one hand, the project is in its current form far from ideal. Electron wastes out of the box a lot of resources on the client-side, shipping an additional a JVM and an embedded web server does not make it better (Why would I need a Browser and a OpenJDK just to use a Java Web application as a desktop application?). If it needs to be Java, why not use Swing or JavaFX? But I can imagine some use cases where this could come in handy, f.e. as inbetween solution before migrating to the cloud.
An improvement to the concept could be done by getting rid of the OpenJDK by using native images of the GraalVM. Getting rid of the browser is currently not possible. If PWAs get available for all platforms and can run applications running on localhost, the browser could eventually be dropped. Currently, an updater functionality is missing, also logging needs to be done manually.

How to build

mvn clean install -Pproduction

The artifacts from the electron build will be put into:

• target\electron\springboot-on-electron-darwin-x64
• target\electron\springboot-on-electron-win32-x64

When using Mac OS or linux, wine is required to build windows (check the maven build for further information).

When using Windows, admin privileges are required to build darwin (check the maven build for further information).

Shipping OpenJDK

Since not all your users have a JVM available via the classpath a OpenJDK 8 will be packed into the electron builds

Documentation

• Configure electron Application

• Configure the electron archs Part1

• Configure the electron archs Part2

• Electron build Part1

• Electron build Part2

• Configure OpenJDK download

• Configure OpenJDK injection

Build

When executing mvn clean install -Pproduction by default the windows (x64) and darwin (x64) will be built.

The rest is currently not supported but adding those shouldn't be too hard but some changes will need to be made at the following files:

• Create 'scripts' for the other electron archs
• Add the new 'scripts' to the maven build
• Download the correct JDK
• Unpack the Downloaded JDK
• Inject downloaded JDK to the electron build
• Use correct JDK at runtime

Pull requests are welcome