maven project as dependency in gradle project

Question

I have a project which is using Gradle as build tool and a second subproject which is using Maven\'s POM. I don\'t have the freedom of changing build tool on the subproject.

Answer 1

you can "fake" including a Maven project like this:

dependencies {
    compile files("vendor/other-proj/target/classes") {
        builtBy "compileMavenProject"
    }
}

task compileMavenProject(type: Exec) {
    workingDir "vendor/other-proj/"
    commandLine "/usr/bin/mvn", "clean", "compile"
}

This way Gradle will execute a Maven build (compileMavenProject) before compiling. But be aware that it is not a Gradle "project" in the traditional sense and will not show up, e.g. if you run gradle dependencies. It is just a hack to include the compiled class files in your Gradle project.

Edit: You can use a similar technique to also include the maven dependencies:

dependencies {
    compile files("vendor/other-proj/target/classes") {
        builtBy "compileMavenProject"
    }
    compile files("vendor/other-proj/target/libs") {
        builtBy "downloadMavenDependencies"
    }
}

task compileMavenProject(type: Exec) {
    workingDir "vendor/other-proj/"
    commandLine "/usr/bin/mvn", "clean", "compile"
}

task downloadMavenDependencies(type: Exec) {
    workingDir "vendor/other-proj/"
    commandLine "/usr/bin/mvn", "dependency:copy-dependencies", "-DoutputDirectory=target/libs"
}