code: @Override
      protected void respond(final AjaxRequestTarget _target)
      {
          final StringValue horizontal = getComponent().getRequest().getRequestParameters().getParameterValue(
                          AjaxStorePositionBehavior.PARAMETER_HORIZONTALPOSITION);
          final StringValue verticalTmp = getComponent().getRequest().getRequestParameters().getParameterValue(
                          AjaxStorePositionBehavior.PARAMETER_VERTICALPOSITION);
          if (!horizontal.isNull()) {
              Configuration.setAttribute(ConfigAttribute.SPLITTERPOSHORIZONTAL, horizontal.toString());
          }
          if (!verticalTmp.isNull()) {
              Configuration.setAttribute(ConfigAttribute.SPLITTERPOSVERTICAL, verticalTmp.toString());
          }
      }
docs: On request the values are stored.
  
  @param _target AjaxRequestTarget