// TODO: subdirectories
// Now sorts file list first (to ensure reproducable MD5 of zip)
static int dir2zip(File inDir, ZipOutputStream outZip, String outPrefix) ctex {
  new L<File> files;
  for (File f : inDir.listFiles())
    if (f.isFile())
      files.add(f);

  sortFilesByName(files);
  for (File f : files) {
    System.out.println("Copying " + f.getName());
    outZip.putNextEntry(new ZipEntry(outPrefix + f.getName()));
    InputStream fin = new FileInputStream(f);
    copyStream(fin, outZip);
    fin.close();
  }
  return files.size();
}

static int dir2zip(File inDir, ZipOutputStream outZip) {
  return dir2zip(inDir, outZip, "");
}

static int dir2zip(String inDir, ZipOutputStream outZip) {
  return dir2zip(new File(inDir), outZip, "");
}

static int dir2zip(File inDir, File zip, S outPrefix default "") ctex {
  mkdirsForFile(zip);
  FileOutputStream fout = new FileOutputStream(zip);
  ZipOutputStream outZip = new ZipOutputStream(fout);
  try {
    ret dir2zip(inDir, outZip, outPrefix);
  } finally {
    outZip.close();
  }
}