static L<File> hotwire_collectJars(File jar) {
  LS libIDs = hotwire_libraryIDsFromJar_deleteJarOnFail(jar);
  L<File> files = ll(jar); // main program has to be first entry! (e.g. for hotwire_makeClassLoader_stickyAndSrcLibs)
  for (S libID : libIDs)
    files.add(loadLibraryOrSrcLib(libID));
  ret files;
}