flowable/flowable-engine · error · ActivitiIllegalArgumentException

Min Priority is null

Error message

Min Priority is null

What it means

Thrown by TaskQueryImpl.taskMinPriority(Integer) in the Flowable 5 engine when the minPriority argument is null. Query builder methods in this library validate arguments eagerly so invalid queries fail at construction time rather than producing broken SQL or an empty/incorrect result set at execution time. Passing null means you cannot express a minimum priority filter, so the library refuses immediately with ActivitiIllegalArgumentException.

Source

Thrown at modules/flowable5-engine/src/main/java/org/activiti/engine/impl/TaskQueryImpl.java:313

    }

    @Override
    public TaskQuery taskPriority(Integer priority) {
        if (priority == null) {
            throw new ActivitiIllegalArgumentException("Priority is null");
        }
        if (orActive) {
            currentOrQueryObject.priority = priority;
        } else {
            this.priority = priority;
        }
        return this;
    }

    @Override
    public TaskQuery taskMinPriority(Integer minPriority) {
        if (minPriority == null) {
            throw new ActivitiIllegalArgumentException("Min Priority is null");
        }
        if (orActive) {
            currentOrQueryObject.minPriority = minPriority;
        } else {
            this.minPriority = minPriority;
        }
        return this;
    }

    @Override
    public TaskQuery taskMaxPriority(Integer maxPriority) {
        if (maxPriority == null) {
            throw new ActivitiIllegalArgumentException("Max Priority is null");
        }
        if (orActive) {
            currentOrQueryObject.maxPriority = maxPriority;
        } else {
            this.maxPriority = maxPriority;

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Pass a concrete Integer value (e.g. taskMinPriority(50)) to taskMinPriority.
2. If the threshold is optional, call taskMinPriority only when the value is non-null: if (min != null) query.taskMinPriority(min);
3. Provide a sane default at the config/DTO layer so the value can never be null.
4. Catch ActivitiIllegalArgumentException at the API boundary and return a 400 with a clear message.

Example fix

// before
int min = config.getMin(); // may be null
query.taskMinPriority(min);

// after
Integer min = config.getMin();
if (min != null) {
    query.taskMinPriority(min);
}

if (minPriority != null) {
    query.taskMinPriority(minPriority);
}

boolean hasMinPriority(Integer v) { return v != null; }

try {
    query.taskMinPriority(minPriority);
} catch (ActivitiIllegalArgumentException e) {
    throw new BadRequestException("Invalid minPriority: " + e.getMessage());
}

When it happens

Trigger: Calling taskQuery.taskMinPriority(null) directly, or passing a variable that was resolved to null (e.g. a config value or request parameter that defaulted to null) into taskMinPriority.

Common situations: Mapping an optional HTTP query parameter straight into taskMinPriority without a default; reading a priority threshold from properties/yaml where the key is absent; deserializing a saved filter DTO where the minPriority field is missing.

Related errors

• Max Priority is null
• text is null
• The command is null
• The config is null
• version is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/18eab86c27720e74. Report an issue: GitHub.