code: public void addExternalJars(File file) throws IllegalAccessException, InvocationTargetException, MalformedURLException {
      assert file.exists() : "Unable to find external file: " + file.getAbsolutePath();
      if( file.isDirectory() ) {
        for( File f : file.listFiles() ) addExternalJars(f);
      } else if( file.getName().endsWith(".jar") ) {
        Log.POST(22, "before (in addExternalJars) invoke _addUrl " + file.toURI().toURL());
        _addUrl.invoke(_systemLoader, file.toURI().toURL());
        Log.POST(22, "after (in addExternalJars) invoke _addUrl " + file.toURI().toURL());
      }
    }
docs: Adds all jars in given directory to the classpath.