code: public void resetPage() {
  
          CmsConfirmDialog dialog = new CmsConfirmDialog(
              Messages.get().key(Messages.GUI_DIALOG_RESET_TITLE_0),
              "<p>" + Messages.get().key(Messages.GUI_DIALOG_PAGE_RESET_0) + "</p>");
          dialog.setCloseText(Messages.get().key(Messages.GUI_BUTTON_CANCEL_TEXT_0));
          dialog.setOkText(Messages.get().key(Messages.GUI_BUTTON_DISCARD_TEXT_0));
          dialog.setHandler(new I_CmsConfirmDialogHandler() {
  
              /**
               * @see org.opencms.gwt.client.ui.I_CmsCloseDialogHandler#onClose()
               */
              public void onClose() {
  
                  deactivateCurrentButton();
                  activateSelection();
              }
  
              /**
               * @see org.opencms.gwt.client.ui.I_CmsConfirmDialogHandler#onOk()
               */
              public void onOk() {
  
                  m_controller.resetPage();
              }
          });
          dialog.center();
      }
docs: Resets the container-page to it's previous state.<p>