Spring Boot "Thinner Fat Jar" - Split jar in 2 (app / libs)-CodePudding

I would like to split my app into 2 fat jars (modules/libraries).

I've checked already the "Spring Boot thin jar project", which loads the dependencies and caches them on first run but I cant make it work with multiple local modules.

Still... I would prefer to make my first approach work. Any ideas?

Gradle 6.9.1 (7.x not working with thin jar)

Spring Boot 2.6.x

Edited (2022-02)

Check my solution below...

CodePudding user response：

Create 2 projects, when build, build to 2 JAR file.
Project 1 (fat JAR) reference to Project 2.
Spring Boot fat JAR (has embed Tomcat), will call another JAR.

CodePudding user response：

I managed to do what I wanted.

For that purpose, I had to extend the bootJar task in gradle into 2 tasks, one for the dependencies, and one for my libraries...

task bootJarDeps(type: org.springframework.boot.gradle.tasks.bundling.BootJar) {
  description "Generates JAR with just dependencies."
  exclude 'com.mypackage.**.jar'
  archiveName 'deps.jar'

  mainClass = 'com.mypackage.App'
  with bootJar
}

The mainClass in the dependencies is useless, but still required for the task.

task bootJarApp(type: org.springframework.boot.gradle.tasks.bundling.BootJar) {
  description "Generates JAR without dependencies."
  include 'com.mypackage.**.jar'
  mainClass = 'com.mypackage.App'
  archiveName 'app.jar'
  with bootJar
}