private boolean checkFilenameExtension(String filename) {
    boolean isAcceptable = false;
    for (int i = 0; i < m_extensionList.size(); i++) {
      String ext = m_extensionList.get(i);
      if (!ext.startsWith("."))
        ext = "." + ext;
      isAcceptable = filename.endsWith(ext);
      if (isAcceptable)
        break;
    }
    return isAcceptable;
  }