apache/maven · error · XMLStreamException

Unable to parse element '{}', must be a long integer

Error message

Unable to parse element '{}', must be a long integer

What it means

Thrown by the Modello-generated StAX reader (template src/mdo/reader.vm) when a model XML field typed as long cannot be parsed by Long.valueOf(String). getLongValue in strict mode wraps the NumberFormatException in a javax.xml.stream.XMLStreamException ('must be a long integer'); non-strict mode returns 0L. Commonly hit on timestamp/size fields expressed in nanoseconds or epoch millis.

Source

Thrown at src/mdo/reader.vm:976

    /**
     * Method getLongValue.
     *
     * @param s a s object.
     * @param strict a strict object.
     * @param parser a parser object.
     * @param attribute a attribute object.
     * @throws XMLStreamException XMLStreamException if
     * any.
     * @return long
     */
    private long getLongValue(String s, String attribute, XMLStreamReader parser, boolean strict)
            throws XMLStreamException {
        if (s != null) {
            try {
                return Long.valueOf(s).longValue();
            } catch (NumberFormatException nfe) {
                if (strict) {
                    throw new XMLStreamException("Unable to parse element '" + attribute + "', must be a long integer", parser.getLocation(), nfe);
                }
            }
        }
        return 0;
    } //-- long getLongValue(String, String, XMLStreamReader, boolean)

    /**
     * Method getRequiredAttributeValue.
     *
     * @param s a s object.
     * @param strict a strict object.
     * @param parser a parser object.
     * @param attribute a attribute object.
     * @throws XMLStreamException XMLStreamException if
     * any.
     * @return String
     */
    private String getRequiredAttributeValue(String s, String attribute, XMLStreamReader parser, boolean strict)

View on GitHub (pinned to e4093d4e12)

Solutions

1. Fix the text at the reported location to a plain integer within long range.
2. Remove grouping separators and unit suffixes from generated files.
3. Re-fetch derived files instead of editing them.
4. Fall back to strict=false when the 0 default is acceptable.

Example fix

<!-- before -->
<size>1,048,576</size>
<!-- after -->
<size>1048576</size>

static boolean isPlainLong(String s) { return s != null && s.matches("[+-]?\\d+") && s.length() < 19; }

try {
    reader.read(in, true);
} catch (XMLStreamException e) {
    log.warn("bad long field at " + e.getLocation(), e);
}

When it happens

Trigger: Strict read of a model XML where a long field holds an empty string, a decimal like '1690000000000.5', a value with unit suffix '1024b', or digits with grouping commas.

Common situations: Hand-tuned metadata or config files with human-friendly but unparseable numbers; copy-paste of values from spreadsheets that insert thin spaces/commas; schema changes between model versions.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• Unable to parse element '{}', must be a byte
• Unable to parse element '{}', must be a floating point numbe
• Unable to parse element '{}', must be an integer
• Unable to parse element '{}', must be a short integer
• Expected root element '${rootTag}' but found '{}'

AI-assisted analysis of apache/maven@e4093d4e12 (2026-08-21). Data as JSON: /api/errors/ec23af47db91117c. Report an issue: GitHub.