flowable/flowable-engine · error · FlowableIllegalArgumentException

deploymentCategory is null

Error message

deploymentCategory is null

What it means

EventDeploymentQueryImpl.deploymentCategory sets an exact category filter on the deployment query. It throws FlowableIllegalArgumentException when deploymentCategory is null because null is not a valid filter value for the SQL query.

Solutions

1. Pass the exact category assigned at deployment time (EventDeploymentBuilder.category(...))
2. Omit the category filter when the category is unknown
3. Null-check or default the category variable before building the query

Example fix

// before
query.deploymentCategory(category); // may be null
// after
if (category != null) {
    query.deploymentCategory(category);
}

if (category == null || category.isEmpty()) { throw new IllegalArgumentException("category required for deploymentCategory()"); }

boolean hasText(String s) { return s != null && !s.trim().isEmpty(); }

try { q.deploymentCategory(category).list(); } catch (FlowableIllegalArgumentException e) { log.warn("category null, skipping filter"); }

When it happens

Trigger: Calling deploymentCategory(null), typically when the category value comes from an optional descriptor, config entry, or map lookup that is absent.

Common situations: Category metadata not configured at deploy time (EventDeploymentBuilder.category not called), config key missing, passing a lookup result straight through without null-checking.

Related errors

• Deployment id is null
• Deployment id is null
• deploymentCategoryExclude is null
• deploymentName is null
• deploymentNameLike is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/76ae79dcd659d55c. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-event-registry/src/main/java/org/flowable/eventregistry/impl/EventDeploymentQueryImpl.java:90

            throw new FlowableIllegalArgumentException("deploymentName is null");
        }
        this.name = deploymentName;
        return this;
    }

    @Override
    public EventDeploymentQueryImpl deploymentNameLike(String nameLike) {
        if (nameLike == null) {
            throw new FlowableIllegalArgumentException("deploymentNameLike is null");
        }
        this.nameLike = nameLike;
        return this;
    }

    @Override
    public EventDeploymentQueryImpl deploymentCategory(String deploymentCategory) {
        if (deploymentCategory == null) {
            throw new FlowableIllegalArgumentException("deploymentCategory is null");
        }
        this.category = deploymentCategory;
        return this;
    }

    @Override
    public EventDeploymentQueryImpl deploymentCategoryNotEquals(String deploymentCategoryNotEquals) {
        if (deploymentCategoryNotEquals == null) {
            throw new FlowableIllegalArgumentException("deploymentCategoryExclude is null");
        }
        this.categoryNotEquals = deploymentCategoryNotEquals;
        return this;
    }

    @Override
    public EventDeploymentQueryImpl parentDeploymentId(String parentDeploymentId) {
        if (parentDeploymentId == null) {
            throw new FlowableIllegalArgumentException("parentDeploymentId is null");

View on GitHub (pinned to d6d39ce1c6)