alibaba/spring-cloud-alibaba · error · ParseException

Unexpected character: {}

Error message

Unexpected character: {}

What it means

Thrown when a field token's first character is none of '?', '*', '/', 'L', or a digit (guard at CronExpression.java:503-504, the final else of storeExpressionVals). The parser cannot begin a field with an operator like '-', 'W', '#', or an unrecognized letter. It is a checked ParseException from the constructor.

Source

Thrown at spring-cloud-alibaba-starters/spring-cloud-starter-alibaba-schedulerx/src/main/java/com/alibaba/cloud/scheduling/schedulerx/util/CronExpression.java:504

		else if (c >= '0' && c <= '9') {
			int val = Integer.parseInt(String.valueOf(c));
			i++;
			if (i >= s.length()) {
				addToSet(val, -1, -1, type);
			}
			else {
				c = s.charAt(i);
				if (c >= '0' && c <= '9') {
					final ValueSet vs = getValue(val, s, i);
					val = vs.value;
					i = vs.pos;
				}
				i = checkNext(i, s, val, type);
				return i;
			}
		}
		else {
			throw new ParseException("Unexpected character: " + c, i);
		}

		return i;
	}

	protected int checkNext(final int pos, final String s, final int val, final int type)
			throws ParseException {

		int end = -1;
		int i = pos;

		if (i >= s.length()) {
			addToSet(val, end, -1, type);
			return i;
		}

		char c = s.charAt(pos);

View on GitHub (pinned to 115d590110)

Solutions

1. Move the operator after a numeric value, e.g. '#1' -> '5#1', 'W' -> '15W'.
2. Remove stray characters; a field must start with '?', '*', '/', 'L', or a digit.
3. Check the cron string encoding (ASCII) and field separators (single spaces).

Example fix

// before
new CronExpression("0 0 0 # * ?");
// after
new CronExpression("0 0 0 ? * 6#3"); // 3rd Friday of the month

// Every field token must start with '?', '*', '/', 'L', or a digit.
private static final Pattern FIELD_START = Pattern.compile("^[?*/L0-9]");
static boolean allFieldStartsValid(String cron) {
    if (cron == null || cron.trim().isEmpty()) return false;
    for (String f : cron.trim().split("\\s+")) {
        if (!FIELD_START.matcher(f).find()) return false;
    }
    return true;
}

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 # * ?")` (day-of-month starts with '#'), or `0 0 0 - * ?`, or `0 0 0 W * ?`, or any non-recognized leading char such as `0 0 0 X * ?`.

Common situations: Operators ('W', '#', 'L') placed at the start of a field instead of after a value (e.g. 'W15' written as 'W' alone), stray punctuation, or non-ASCII/letter typos. Also locale/encoding artifacts in config files.

Related errors

• '/' must be followed by an integer.
• Unexpected end of string.
• Increment > 60 : {}
• Increment > 24 : {}
• Increment > 31 : {}

AI-assisted analysis of alibaba/spring-cloud-alibaba@115d590110 (2026-08-14). Data as JSON: /api/errors/e346d3655f033c5b. Report an issue: GitHub.