createTarGz.kt

fun createTarGz(`in`: File, out: File) {
	val fOut = FileOutputStream(out)
	val bOut = BufferedOutputStream(fOut)
	val gzOut = GzipCompressorOutputStream(bOut)
	TarArchiveOutputStream(gzOut).use {
		addFileToTarGz(it, `in`, "")
		it.finish()
	}
}

private fun addFileToTarGz(tOut: TarArchiveOutputStream, out: File, base: String) {
	val entryName = base + out.name
	val tarEntry = TarArchiveEntry(out, entryName)
	tOut.putArchiveEntry(tarEntry)
	
	if (out.isFile) {
		FileInputStream(out).use {
			IOUtils.copy(it, tOut)
			tOut.closeArchiveEntry()
		}
	} else {
		tOut.closeArchiveEntry()
		out.listFiles()?.forEach {
			addFileToTarGz(tOut, it, entryName + "/")
		}
	}
}