gistfile1.txt

public class KawaCompileTask extends DefaultTask {
  @InputFiles
  Set<File> source = [] as Set;

  String classpath;

  @TaskAction
  void compile() {
    println "compiling kawa sources..."
    project.exec {
      //enviroment["CLASSPATH"] = classpath
      executable = "kawa"
      List <File> files = source.collect { File source ->
        if (!source.isDirectory())
          return source
        return project.fileTree(source) {
          include "**/*.scm"
        }.files
      }.flatten()

      println "found: "+files.size()
      if (files.size() == 0)
        return 0

      args "-d", outputDir, "-C"
      args += files
      println "args: "+args
    }
  }

}

task kawacompile(type: KawaCompileTask) {
  classpath = "/opt/android-studio/sdk//platforms/android-19/android.jar"
  source += file("src/main/kawa")
  outputDir = file("$buildDir/kawa")
}