if (documentFilter != null)
if (length == 0 && (text == null || text.length() == 0)) return;  if (documentFilter == null) {       remove(offset, length); insertString(offset, text, attributes); } else
  public void replace(int offset, int length, String text,		      AttributeSet attributes)    throws BadLocationException  {    if (documentFilter != null)      documentFilter.replace(getBypass(), offset, length, text, attributes);    else      replaceImpl(offset, length, text, attributes);  }