jeecgboot/JeecgBoot · error · ParseException

Unexpected character: {c}

Error message

Unexpected character: {c}

What it means

The terminal else of storeExpressionVals: the current character c matched none of the recognized branches (not A-Z alpha, not '?', not '*' or '/', not 'L', not a digit 0-9). Any unrecognised symbol - punctuation, lowercase, special chars - lands here. It is the fallback for truly unexpected characters at a position where a value was expected.

Source

Thrown at jeecg-boot/jeecg-server-cloud/jeecg-visual/jeecg-cloud-xxljob/src/main/java/com/xxl/job/admin/business/scheduler/cron/CronExpression.java:720

            }
            return i;
        } 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') {
                    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;
    }

    private void checkIncrementRange(int incr, int type, int idxPos) throws ParseException {
        if (incr > 59 && (type == SECOND || type == MINUTE)) {
            throw new ParseException("Increment >= 60 : " + incr, idxPos);
        } else if (incr > 23 && (type == HOUR)) {
            throw new ParseException("Increment >= 24 : " + incr, idxPos);
        } else if (incr > 31 && (type == DAY_OF_MONTH)) {
            throw new ParseException("Increment >= 31 : " + incr, idxPos);
        } else if (incr > 7 && (type == DAY_OF_WEEK)) {
            throw new ParseException("Increment >= 7 : " + incr, idxPos);
        } else if (incr > 12 && (type == MONTH)) {
            throw new ParseException("Increment >= 12 : " + incr, idxPos);
        }
    }

View on GitHub (pinned to 96fb33f5ec)

Solutions

1. Inspect the character at the reported position and replace it with a valid token (digit, '*', '?', '/', '-', 'L', or 'W' where supported).
2. Use ',' only between list elements inside a field, not at the start/end.
3. Uppercase all letter modifiers ('L', 'W'); the parser only enters the alpha branch for A-Z.
4. Strip non-cron characters from pasted expressions before parsing.

Example fix

// before - stray '.' in day-of-month
String cron = "0 0 0 5.5 * ?";  // Unexpected character: .

// after - valid list or single value
String cron = "0 0 0 5,15 * ?";

// Whitelist the allowed character set for the whole expression before parsing.
private static final java.util.regex.Pattern CRON_CHARSET =
    java.util.regex.Pattern.compile("^[0-9*?/\\-,LW# A-Za-z]+$");

public static String validateCharset(String expr) {
    if (expr == null || !CRON_CHARSET.matcher(expr).matches()) {
        return "expression contains characters outside the allowed cron charset: " + expr;
    }
    return null;
}

public static boolean usesAllowedCronCharset(String expr) {
    return expr != null && expr.matches("[0-9*?/\\-,LW# A-Za-z]+");
}

try {
    new CronExpression(expr);
} catch (ParseException e) {
    if (e.getMessage().startsWith("Unexpected character")) {
        return "Remove the symbol at the reported position; only 0-9 * ? / - , L W # and letters are allowed. " + e.getMessage();
    }
    throw e;
}

When it happens

Trigger: Characters like '@', '#', '!', '.', ',', lowercase letters, or a stray symbol in a value position: '0 0 0 ,5 * * ?' (leading comma), '0 0 0 #5 * * ?', '0 0 0 5.5 * * ?', or lowercase 'l' instead of 'L'.

Common situations: Locale-specific separators (e.g. decimal comma), stray punctuation from copy/paste, lowercase 'l'/'w' that should be uppercase, or a typo inserting a symbol.

Related errors

• Illegal cron expression format ({e})
• Invalid Month value: '{sub}'
• Invalid Day-of-Week value: '{sub}'
• A numeric value between 1 and 5 must follow the '#' option
• Illegal characters for this position: '{sub}'

AI-assisted analysis of jeecgboot/JeecgBoot@96fb33f5ec (2026-08-14). Data as JSON: /api/errors/d32bc5e94a442e2c. Report an issue: GitHub.