jeecgboot/JeecgBoot · error · ParseException

'W' option is not valid here. (pos=${i})

Error message

'W' option is not valid here. (pos=${i})

What it means

Thrown when the 'W' (nearest weekday) modifier appears in any cron field other than day-of-month. The 'W' character instructs the scheduler to fire on the closest weekday (Mon–Fri) to the given day number, and it is only meaningful for the day-of-month field. Using it in second, minute, hour, day-of-week, month, or year fields is a syntax error.

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:769

        char c = s.charAt(pos);

        if (c == 'L') {
            if (type == DAY_OF_WEEK) {
                if(val < 1 || val > 7)
                    throw new ParseException("Day-of-Week values must be between 1 and 7", -1);
                lastDayOfWeek = true;
            } else {
                throw new ParseException("'L' option is not valid here. (pos=" + i + ")", i);
            }
            TreeSet<Integer> set = getSet(type);
            set.add(val);
            i++;
            return i;
        }

        if (c == 'W') {
            if (type != DAY_OF_MONTH) {
                throw new ParseException("'W' option is not valid here. (pos=" + i + ")", i);
            }
            if(val > 31)
                throw new ParseException("The 'W' option does not make sense with values larger than 31 (max number of days in a month)", i);
            nearestWeekdays.add(val);
            i++;
            return i;
        }

        if (c == '#') {
            if (type != DAY_OF_WEEK) {
                throw new ParseException("'#' option is not valid here. (pos=" + i + ")", i);
            }
            i++;
            try {
                nthDayOfWeek = Integer.parseInt(s.substring(i));
                if (nthDayOfWeek < 1 || nthDayOfWeek > 5) {
                    throw new Exception();
                }

View on GitHub (pinned to 96fb33f5ec)

Solutions

1. Ensure the 'W' modifier appears only in the day-of-month field (the 4th field in a 6-field cron, or 3rd of 6 before year).
2. Verify field count and ordering: seconds minutes hours day-of-month month day-of-week [year].
3. Use '?' in the day-of-week field when specifying a day-of-month with 'W'.

Example fix

// before
String cron = "0 0 0 ? * 15W";  // 'W' is in day-of-week position — wrong
// after
String cron = "0 0 0 15W * ?";  // 'W' in day-of-month position

// Ensure 'W' only appears in the day-of-month field (field index 3)
String[] fields = cronExpr.split("\\s+");
for (int f = 0; f < fields.length; f++) {
    if (fields[f].contains("W") && f != 3) {
        throw new IllegalArgumentException("'W' is only valid in day-of-month field");
    }
}

boolean isWOnlyInDayOfMonth(String cron) {
    String[] fields = cron.trim().split("\\s+");
    for (int f = 0; f < fields.length; f++) {
        if (fields[f].contains("W") && f != 3) return false;
    }
    return true;
}

try {
    CronExpression cron = new CronExpression(expr);
} catch (ParseException e) {
    if (e.getMessage().contains("'W' option is not valid here")) {
        // 'W' was placed in a non-day-of-month field
    }
    throw e;
}

When it happens

Trigger: A cron expression containing 'W' after a numeric value where type != DAY_OF_MONTH — e.g., day-of-week field '5W', hour field '10W', or month field '3W'.

Common situations: Developer confuses day-of-week and day-of-month field positions; expression has an extra or missing field causing misalignment; copy-paste error placing 'W' in the wrong field.

Related errors

• Day-of-Week values must be between 1 and 7
• 'L' option is not valid here. (pos=${i})
• The 'W' option does not make sense with values larger than 3
• '#' option is not valid here. (pos=${i})
• Unexpected character '${c}' after '/'

AI-assisted analysis of jeecgboot/JeecgBoot@96fb33f5ec (2026-08-14). Data as JSON: /api/errors/3470c51099805d93. Report an issue: GitHub.