flowable/flowable-engine · error · FlowableException

Error converting timer expression

Error message

Error converting timer expression

What it means

Thrown when the StAX reader cannot read the text of a <timerExpression> element while converting a CMMN timer event listener. The expression would be set via setTimerExpression on the TimerEventListener; an XMLStreamException is wrapped in this FlowableException.

Source

Thrown at modules/flowable-cmmn-converter/src/main/java/org/flowable/cmmn/converter/TimerExpressionXmlConverter.java:46

    @Override
    public String getXMLElementName() {
        return CmmnXmlConstants.ELEMENT_TIMER_EXPRESSION;
    }
    
    @Override
    public boolean hasChildElements() {
        return false;
    }

    @Override
    protected CmmnElement convert(XMLStreamReader xtr, ConversionHelper conversionHelper) {
        try {
            String expression = xtr.getElementText();
            if (StringUtils.isNotEmpty(expression) && conversionHelper.getCurrentCmmnElement() instanceof TimerEventListener timerEventListener) {
                timerEventListener.setTimerExpression(expression);
            }
        } catch (XMLStreamException e) {
            throw new FlowableException("Error converting timer expression", e);
        }
        return null;
    }
    
}

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Validate and repair the <timerExpression> element in the CMMN XML.
2. Inspect the cause XMLStreamException for the exact offset.
3. Ensure the element is well-formed, e.g. <timerExpression>PT1H</timerExpression>.
4. Re-export the model from the modeling tool.

Example fix

// before
<timerExpression>PT1
// after
<timerExpression>PT1H</timerExpression>

javax.xml.validation.Validator v = schema.newValidator();
v.validate(new StreamSource(cmmnXml));

try {
    CmmnModel model = converter.convertToCmmnModel(in);
} catch (FlowableException e) {
    throw new IllegalStateException("Invalid <timerExpression> element: " + e.getCause(), e);
}

When it happens

Trigger: Parsing CMMN XML with a timer event listener whose <timerExpression> element is malformed or unreadable (unclosed tags, invalid chars, encoding problems).

Common situations: Hand-edited timer expressions; ISO duration strings containing invalid characters; truncated XML files.

Understand the failure class

Background: "failed to read file", EACCES, ENOENT and "could not read <path>" errors: when a program can't read a file from disk — this error's family across 49 libraries.

Related errors

• Error while reading {ATTRIBUTE_ELEMENT_NAME} extension eleme
• Error converting process reference expression
• Error converting standard event
• Error converting text annotation
• Timer expression '${timerEventListener.getTimerExpression()}

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/13e5bfe5401b0cfd. Report an issue: GitHub.