Gradle create a jar file from an android library module

android-library-jar.gradle

android.libraryVariants.all { variant ->
    def name = variant.buildType.name
    if (name.indexOf("debug") > -1) {
        return; // Skip debug builds.
    }
    def task = project.tasks.create "jar${name.capitalize()}", Jar
    task.baseName = "${project.name}-${rootProject.version}"
    task.dependsOn variant.javaCompile
    task.from variant.javaCompile.destinationDir
    artifacts.add('archives', task);
}