throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);
throw new DomDOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR);
  public void insertData(int offset, String arg)  {    if (isReadonly())      {      throw new DomEx(DomEx.NO_MODIFICATION_ALLOWED_ERR);      }    char[] raw = text.toCharArray();    char[] tmp = arg.toCharArray ();    char[] buf = new char[raw.length + tmp.length];        try      {        System.arraycopy(raw, 0, buf, 0, offset);        System.arraycopy(tmp, 0, buf, offset, tmp.length);        System.arraycopy(raw, offset, buf, offset + tmp.length,                         raw.length - offset);        String value = new String(buf);        mutating(value);        text = value;      }    catch (IndexOutOfBoundsException x)      {        throw new DomEx(DomEx.INDEX_SIZE_ERR);      }  }