flowable/flowable-engine · error · ActivitiIllegalArgumentException

Task namelike is null

Error message

Task namelike is null

What it means

Fluent-setter validation in flowable5 TaskQueryImpl.taskNameLike: a null LIKE pattern was passed to the task-name filter and rejected as caller error.

Solutions

1. Guard the call: only invoke taskNameLike when the value is non-null
2. Use a null-safe default such as a wildcard only when a pattern is genuinely provided
3. Let the query builder be conditional: if (pattern != null) query.taskNameLike(pattern);

Example fix

// before
String nameLike = params.get("nameLike");
query.taskNameLike(nameLike);
// after
String nameLike = params.get("nameLike");
if (nameLike != null) {
    query.taskNameLike(nameLike);
}

Objects.requireNonNull(nameLike, "taskNameLike pattern must not be null"); // or skip the call entirely

void addNameLikeFilter(TaskQuery query, String nameLike) {
    if (nameLike != null) {
        query.taskNameLike(nameLike);
    }
}

try {
    query.taskNameLike(pattern);
} catch (org.activiti.engine.ActivitiIllegalArgumentException e) {
    // pattern was null: apply no name filter or return 400
}

When it happens

Trigger: Calling taskNameLike(null), typically when the value comes from a variable/optional field that was never initialized.

Common situations: Binding a search-form field straight into taskNameLike without checking presence; a Map/DTO lookup that returns null for an absent key; Optional handled with orElse(null).

Related errors

• Description is null
• None of the given process categories can be null
• Priority is null
• Task descriptionlike is null
• Task descriptionLikeIgnoreCase is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/75c6eafeb9d4336a. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable5-engine/src/main/java/org/activiti/engine/impl/TaskQueryImpl.java:232

        final int nameListSize = nameList.size();
        final List<String> caseIgnoredNameList = new ArrayList<>(nameListSize);
        for (String name : nameList) {
            caseIgnoredNameList.add(name.toLowerCase());
        }

        if (orActive) {
            this.currentOrQueryObject.nameListIgnoreCase = caseIgnoredNameList;
        } else {
            this.nameListIgnoreCase = caseIgnoredNameList;
        }
        return this;
    }

    @Override
    public TaskQueryImpl taskNameLike(String nameLike) {
        if (nameLike == null) {
            throw new ActivitiIllegalArgumentException("Task namelike is null");
        }

        if (orActive) {
            currentOrQueryObject.nameLike = nameLike;
        } else {
            this.nameLike = nameLike;
        }
        return this;
    }

    @Override
    public TaskQuery taskNameLikeIgnoreCase(String nameLikeIgnoreCase) {
        if (nameLikeIgnoreCase == null) {
            throw new ActivitiIllegalArgumentException("Task nameLikeIgnoreCase is null");
        }

        if (orActive) {
            currentOrQueryObject.nameLikeIgnoreCase = nameLikeIgnoreCase.toLowerCase();

View on GitHub (pinned to d6d39ce1c6)