Java platform plugin do not use all dependencies

Question

Intro

The following situation:

I'm working on multiple dependent Java projects that are built using the Gradle build system.

There are several dependencies that I want to be resolved via the java platform plugin for gradle and a resulting BOM (Bill of Materials).

Example & Problem:

In the example below there is a build.gradle for the platform BOM that is used as a dependency resolver for all projects. There are two constraints in this BOM: One for an implementation dependency named foo an another for compile dependency named bar.

// build.gradle for BOM "my-utility-bom"
// ...
dependencies {
    constraints {
        api("some.implementation.dependency:foo:3.4.1")
        api("some.compile.dependency:bar:1.2.0")
    }
}
// ...

Both dependencies are then used inside a project by applying the platform keyword to the given bom project. Because I would like to use the two contraints from the bom as dependencies, I then use implementation on the platform project and compileOnly the same way.

// build.gradle for java project
//...
dependencies {
    implementation(platform(project(":my-utility-bom")))
    compileOnly(platform(project(":my-utility-bom")))

    implementation("some.implementation.dependency:foo")
    compileOnly("some.compile.dependency:bar")
}

// ...

After that, all dependencies are pulled in as both, a implementation dependency AND compileOnly dependency. But I just want the one depenency as an implementation dependency and the other as a compileOnly dependency.

Question

Is possible to only pull specific dependencies as implementation or compileOnly dependency without the use of separate BOMs for compile and implementation dependencies?

Answer 1

I tried out an example similar to yours and dependencies get resolved as expected. In your case when running gradle dependencies:

• implementation configuration will import only some.implementation.dependency:foo
• compileOnly configuration will import some.compile.dependency:bar

Then this will be resolved in

• compileClasspath importing both resolved dependencies some.implementation.dependency:foo:3.4.1 and some.compile.dependency:bar:1.2.0
• runtimeClasspath will import only some.implementation.dependency:foo:3.4.1

I would say that your configuration is correct. In case your dependency tree say otherwise, then maybe there are dependencies applied somehow additionally not visible from your example. Would be helpful to see your actual case. Note I used Gradle 7.0. In this repository there is whole example.

This graph helped me understand how different configuration will be resolved