mybatis if-else

"<choose>\n" +
            "    <when test=\" IS_HIS != null and IS_HIS !=''\">\n" +
            "    from t_Ows_Compelete_Rfc t\n" +
            "    </when>\n" +
            "    <otherwise>\n" +
            "  from t_Ows_Actualtime_Rfc t\n" +
            "    </otherwise>\n" +
            "</choose>\n" +