Dependencies specified with `implementation` configuration in Gradle build not put into Spring Boot fat jar

Question

I'm working on some legacy code with the following versions:

• Gradle 4.10.2
• Spring Boot 1.5.16.RELEASE

I was expecting that any dependencies I specify with the implementation dependency configuration would be placed in the Spring Boot fat jar when I execute the assemble task. However they are not .

I've resorted to using the deprecated compile dependency configuration for now, but I'm confused as to why implementation doesn't work.

Simplified build.gradle is as follows:

plugins {
    id 'java'
    id "org.springframework.boot" version "1.5.16.RELEASE"
}

group 'org.example'
version '1.0-SNAPSHOT'

sourceCompatibility = 1.8

repositories {
    mavenLocal()
    mavenCentral()
}

dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'

    implementation 'org.apache.commons:commons-lang3:3.10'

    testCompile group: 'junit', name: 'junit', version: '4.12'
}

In the example above, I would have expected commons-lang3-3.10.jar to be put inside the fat jar when I execute the assemble Gradle task. It does not!

Answer 1

The most likely explanation is that this version of the Spring boot plugin did not support the reworked configurations of the Gradle java plugins.