static class JavaXClassLoader extends URLClassLoader {

  S progID;

  L<File> files;

  Set<S> triedToLoad = synchroSet();

  Set<Class> loadedClasses = synchroSet();

  L additionalResolvers; // each is a func(S className) -> InputStream

  bool retired;

  O retiredMarker;

  *(S progID, L<File> files) {

    this(progID, files, getSystemClassLoader());

  }

  *(S progID, L<File> files, ClassLoader parent) {

    super(new URL[0], parent);

    this.progID = progID;

    this.files = files;

    ctex {

      for (File f : files)

        addURL(f.toURI().toURL());

    }

    fixACCInClassLoader(this);

  }

  protected Class<?> findClass(S name) throws ClassNotFoundException {

    bool triedBefore = !triedToLoad.add(name);

    try {

      Class<?> c = super.findClass(name);

      loadedClasses.add(c);

      if (eq(name, "main"))

        callOpt(javax(), 'registerAMainClass, c);

      ret c;

    } catch (ClassNotFoundException e) {

      throw new ClassNotFoundException("Class " + name + " not found in " + joinWithComma(map(f f2s, files)) + " (progID=" + progID + ")"

        + (triedBefore ? ", tried to load before" : ""), e);

    }

  }

  toString {

    ret "JavaXClassLoader[" + systemHashCodeHex(this) + "] - " + progID;

  }

  public InputStream getResourceAsStream(String name) {

    fOr (O f : additionalResolvers)

      try object InputStream in = cast callF(f, name);

    ret super.getResourceAsStream(name);

  }

}