flowable/flowable-engine · error · ActivitiIllegalArgumentException

key is null

Error message

key is null

What it means

DeploymentQueryImpl.processDefinitionKey() throws ActivitiIllegalArgumentException when the key argument is null. Even though this is a DeploymentQuery, it can filter by process definition key, and that key must be a concrete non-null value to build the predicate.

Source

Thrown at modules/flowable5-engine/src/main/java/org/activiti/engine/impl/DeploymentQueryImpl.java:126

    @Override
    public DeploymentQueryImpl deploymentTenantIdLike(String tenantIdLike) {
        if (tenantIdLike == null) {
            throw new ActivitiIllegalArgumentException("deploymentTenantIdLike is null");
        }
        this.tenantIdLike = tenantIdLike;
        return this;
    }

    @Override
    public DeploymentQueryImpl deploymentWithoutTenantId() {
        this.withoutTenantId = true;
        return this;
    }

    @Override
    public DeploymentQueryImpl processDefinitionKey(String key) {
        if (key == null) {
            throw new ActivitiIllegalArgumentException("key is null");
        }
        this.processDefinitionKey = key;
        return this;
    }

    @Override
    public DeploymentQueryImpl processDefinitionKeyLike(String keyLike) {
        if (keyLike == null) {
            throw new ActivitiIllegalArgumentException("keyLike is null");
        }
        this.processDefinitionKeyLike = keyLike;
        return this;
    }

    // sorting ////////////////////////////////////////////////////////

    @Override
    public DeploymentQuery orderByDeploymentId() {

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Pass a non-null process definition key
2. Guard the call: only add the filter when the key is present
3. Validate the key at the API boundary before invoking the query
4. Fix the upstream lookup that should have produced the key

Example fix

// before
DeploymentQuery q = repositoryService.createDeploymentQuery().processDefinitionKey(defKey);
// after
DeploymentQuery q = repositoryService.createDeploymentQuery();
if (defKey != null) {
    q = q.processDefinitionKey(defKey);
}

if (processDefinitionKey == null) { throw new IllegalArgumentException("processDefinitionKey must not be null"); }
repositoryService.createDeploymentQuery().processDefinitionKey(processDefinitionKey)...

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

try {
    repositoryService.createDeploymentQuery().processDefinitionKey(key).list();
} catch (ActivitiIllegalArgumentException e) {
    log.error("process definition key was null", e);
}

When it happens

Trigger: Calling repositoryService.createDeploymentQuery().processDefinitionKey(null), typically when the definition key was resolved from a nullable variable, request parameter, or a failed lookup on a process definition entity.

Common situations: Pages that query deployments for an optional selected process definition; keys read from process variables or forms that were never set; refactor replacing a hardcoded key with a parameter defaulting to null.

Related errors

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

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/0ba2e3d693d7780e. Report an issue: GitHub.