alibaba/spring-cloud-alibaba · error · ParseException

Support for specifying 'L' and 'LW' with other days of the m

Error message

Support for specifying 'L' and 'LW' with other days of the month is not implemented

What it means

Thrown during CronExpression.buildExpression while parsing the DAY_OF_MONTH field: if the token contains 'L' (last day / last weekday 'LW'), is longer than one char, and also contains a comma (a list of days), the parser refuses it with ParseException. Quartz does not implement combining the 'L'/'LW' modifier with other comma-separated day values.

Source

Thrown at spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-schedulerx/src/main/java/com/alibaba/cloud/scheduling/schedulerx/util/CronExpression.java:271

			seconds = new TreeSet<>();
			minutes = new TreeSet<>();
			hours = new TreeSet<>();
			daysOfMonth = new TreeSet<>();
			months = new TreeSet<>();
			daysOfWeek = new TreeSet<>();
			years = new TreeSet<>();

			int exprOn = SECOND;

			final StringTokenizer exprsTok = new StringTokenizer(expression, " \t",
					false);

			while (exprsTok.hasMoreTokens() && exprOn <= YEAR) {
				final String expr = exprsTok.nextToken().trim();

				// throw an exception if L is used with other days of the month
				if (exprOn == DAY_OF_MONTH && expr.indexOf('L') != -1 && expr.length() > 1 && expr.contains(",")) {
					throw new ParseException("Support for specifying 'L' and 'LW' with other days of the month is not implemented", -1);
				}
				// throw an exception if L is used with other days of the week
				if (exprOn == DAY_OF_WEEK && expr.indexOf('L') != -1 && expr.length() > 1 && expr.contains(",")) {
					throw new ParseException("Support for specifying 'L' with other days of the week is not implemented", -1);
				}
				if (exprOn == DAY_OF_WEEK && expr.indexOf('#') != -1 && expr.indexOf('#', expr.indexOf('#') + 1) != -1) {
					throw new ParseException("Support for specifying multiple \"nth\" days is not implemented.", -1);
				}

				final StringTokenizer vTok = new StringTokenizer(expr, ",");
				while (vTok.hasMoreTokens()) {
					final String v = vTok.nextToken();
					storeExpressionVals(0, v, exprOn);
				}

				exprOn++;
			}

View on GitHub (pinned to 115d590110)

Solutions

1. Split into two jobs/triggers: one for the fixed days (e.g. '0 0 0 15 * ?') and one for the last day ('0 0 0 L * ?').
2. If you only need the last day, use 'L' alone; if the last weekday, use 'LW' alone — without a comma list.
3. Validate the cron with the same CronExpression class at config-load time to catch it before deployment.

Example fix

# before (invalid: L mixed with list)
0 0 0 15,L * ?

# after (two separate triggers)
0 0 0 15 * ?   # the 15th
0 0 0 L * ?    # the last day of month

static String validateCron(String cron) throws ParseException {
    // trial-parse at config/validation time
    new com.alibaba.cloud.scheduling.schedulerx.util.CronExpression(cron);
    return cron;
}

// reject day-of-month lists containing L/LW before parsing
static boolean isValidDom(String dom) {
    boolean hasL = dom.indexOf('L') != -1;
    return !(hasL && dom.length() > 1 && dom.contains(","));
}

try {
    CronExpression expr = new CronExpression(cron);
} catch (ParseException e) {
    // e.g. "Support for specifying 'L' and 'LW' with other days of the month is not implemented"
    throw new IllegalArgumentException("Invalid cron '" + cron + "': " + e.getMessage(), e);
}

When it happens

Trigger: A cron whose day-of-month field is a list including L or LW, e.g. '0 0 0 15,L * ?' or '0 0 0 1,LW * ?'. The check at CronExpression.java:270-272 matches DAY_OF_MONTH && indexOf('L')!=-1 && length()>1 && contains(',').

Common situations: Wanting 'every 15th and the last day of the month' and writing '15,L'; copy-pasting a Unix-style cron (5-field) into the 6/7-field Quartz format and appending a stray list; misunderstanding that L cannot be mixed in a list.

Related errors

• Support for specifying 'L' with other days of the week is no
• Support for specifying multiple "nth" days is not implemente
• Unexpected end of expression.
• Support for specifying both a day-of-week AND a day-of-month
• Illegal cron expression format ({})

AI-assisted analysis of alibaba/spring-cloud-alibaba@115d590110 (2026-08-14). Data as JSON: /api/errors/90a104466ea2cb34. Report an issue: GitHub.