protected int before(Writer out) throws Exception {
    super.before(out);

    UiUtil.writeOpenStartTag(out, "tbody");
    UiUtil.writeAttribute(out, "id", globalId);
    UiUtil.writeCloseStartTag(out);

    return EVAL_BODY_INCLUDE;
  }
  protected int before(Writer out) throws Exception {
    super.before(out);

    // Error check
    if (getAttribute(ID_KEY_REQUEST, PageContext.REQUEST_SCOPE) != null)
      throw new UiException("System form cannot be nested");

    // Compute id
    id = id == null ? UiSystemFormTag.generateId(pageContext) : id;

    pushAttribute(ID_KEY_REQUEST, id, PageContext.REQUEST_SCOPE);
    pushAttribute(SYSTEM_FORM_ID_KEY, id, PageContext.REQUEST_SCOPE);

    // Write form
    UiUtil.writeOpenStartTag(out, "form");
    UiUtil.writeAttribute(out, "id", id);
    UiUtil.writeAttribute(out, "name", id);
    UiUtil.writeAttribute(out, "method", method);
    UiUtil.writeAttribute(out, "enctype", enctype);
    UiUtil.writeAttribute(out, "accept-charset", getAcceptCharset());
    UiUtil.writeAttribute(out, "action", getFormAction());
    UiUtil.writeAttribute(out, "style", "margin: 0px");
    UiUtil.writeCloseStartTag(out);

    // Script
    // Initialize the uiProperties object for this systemform
    // This object will store validators for UiLib forms contained in this systemform.
    UiUtil.writeOpenStartTag(out, "script");
    UiUtil.writeAttribute(out, "type", "text/javascript");
    UiUtil.writeCloseStartTag(out);
    out.write("uiSystemFormContext(");
    UiUtil.writeScriptString(out, id);
    out.write(");\n");
    UiUtil.writeEndTag(out, "script");

    // Continue
    return EVAL_BODY_INCLUDE;
  }