code: private boolean validateFieldValues(final AjaxRequestTarget _target)
          throws EFapsException
      {
          AjaxSubmitCloseButton.LOG.trace("entering validateFieldValues");
          boolean ret = true;
          final ICmdUIObject uiobject = (ICmdUIObject) getPage().getDefaultModelObject();
          final StringBuilder html = new StringBuilder();
          html.append("<table class=\"eFapsValidateFieldValuesTable\">");
          if (uiobject instanceof UIForm) {
              final UIForm uiform = (UIForm) uiobject;
              ret = evalFormElement(_target, html, uiform);
          }
          if (!ret) {
              html.append("</table>");
              showDialog(_target, html.toString(), true, false);
          }
          return ret;
      }
docs: Method to validate the values for fields.
  @param _target   AjaxRequestTarget
  @return true if validation was valid, else false
  @throws EFapsException on error