alibaba/spring-cloud-alibaba · error · ParseException

Increment > 31 : {}

Error message

Increment > 31 : {}

What it means

Thrown when a step value after '/' exceeds 31 in the DAY_OF_MONTH field (guard at CronExpression.java:441-442). Day-of-month steps are capped at 31 because no month has more days.

Source

Thrown at spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-schedulerx/src/main/java/com/alibaba/cloud/scheduling/schedulerx/util/CronExpression.java:442

				i++;
				if (i >= s.length()) {
					throw new ParseException("Unexpected end of string.", i);
				}

				incr = getNumericValue(s, i);

				i++;
				if (incr > 10) {
					i++;
				}
				if (incr > 59 && (type == SECOND || type == MINUTE)) {
					throw new ParseException("Increment > 60 : " + incr, i);
				}
				else if (incr > 23 && (type == HOUR)) {
					throw new ParseException("Increment > 24 : " + incr, i);
				}
				else if (incr > 31 && (type == DAY_OF_MONTH)) {
					throw new ParseException("Increment > 31 : " + incr, i);
				}
				else if (incr > 7 && (type == DAY_OF_WEEK)) {
					throw new ParseException("Increment > 7 : " + incr, i);
				}
				else if (incr > 12 && (type == MONTH)) {
					throw new ParseException("Increment > 12 : " + incr, i);
				}
			}
			else {
				incr = 1;
			}

			addToSet(ALL_SPEC_INT, -1, incr, type);
			return i;
		}
		else if (c == 'L') {
			i++;
			if (type == DAY_OF_MONTH) {

View on GitHub (pinned to 115d590110)

Solutions

1. Use a day-of-month step <= 31, e.g. '*/32' -> '*/15'.
2. For end-of-month behavior, prefer the 'L' or 'L-N' construct instead of a large step.
3. Verify all six fields are present so the step sits in the intended field.

Example fix

// before
new CronExpression("0 0 0 */32 * ?");
// after
new CronExpression("0 0 0 */15 * ?"); // every 15 days

static boolean stepWithin(String field, int max) {
    int slash = field.indexOf('/');
    if (slash < 0) return true;
    try { return Integer.parseInt(field.substring(slash + 1)) <= max; }
    catch (NumberFormatException e) { return false; }
}

try {
    CronExpression cron = new CronExpression(raw);
} catch (ParseException e) {
    throw new IllegalArgumentException("Invalid cron expression: " + raw, e);
}

When it happens

Trigger: `new CronExpression("0 0 0 */32 * ?")` (day-of-month step 32) or any step > 31 in the day-of-month position.

Common situations: Developer intends 'last few days' logic or copies a step from another field. A field-count error (missing seconds) is a frequent root cause, placing a large step into day-of-month.

Related errors

• Increment > 60 : {}
• Increment > 24 : {}
• Increment > 7 : {}
• Increment > 12 : {}
• Offset from last day must be <= 30

AI-assisted analysis of alibaba/spring-cloud-alibaba@115d590110 (2026-08-14). Data as JSON: /api/errors/0eb695178053ef74. Report an issue: GitHub.