alibaba/spring-cloud-alibaba · error · ParseException

Increment > 24 : {}

Error message

Increment > 24 : {}

What it means

Thrown when a step value after '/' exceeds 23 in the HOUR field (guard at CronExpression.java:438-439). Hour steps must be within the 0-23 hour range; the message reports '> 24' though the code checks `incr > 23`.

Source

Thrown at spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-schedulerx/src/main/java/com/alibaba/cloud/scheduling/schedulerx/util/CronExpression.java:439

			}
			c = s.charAt(i);
			if (c == '/') { // is an increment specified?
				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;
		}

View on GitHub (pinned to 115d590110)

Solutions

1. Use a step <= 23 for hours, e.g. '*/24' -> '*/12'.
2. For 'every 24 hours / every day at a time', use a fixed hour like '0 0 12 * * ?' instead of a step.
3. Recount the six fields to ensure the step is actually in the hours position.

Example fix

// before
new CronExpression("0 0 */24 * * ?");
// after
new CronExpression("0 0 */12 * * ?"); // every 12 hours

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 */24 * * ?")` (hour step 24) or any `*/NN`/`N/NN` in the hours field with NN > 23.

Common situations: Wanting 'every 24 hours' which cron cannot express as a single hour step, or an off-by-one from a 1-based UI. Also a field-shift bug where a day-of-month value lands in the hours field.

Related errors

• Increment > 60 : {}
• Increment > 31 : {}
• 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/8bd518d073e40fdb. Report an issue: GitHub.