flowable/flowable-engine · error · FlowableIllegalArgumentException

Execution id is null

Error message

Execution id is null

What it means

executionId() pins the query to a single execution by its database ID. Flowable throws FlowableIllegalArgumentException when the ID string is null, since an ID equality predicate cannot be formed from null. Failing fast prevents issuing a query that would silently match nothing or everything.

Solutions

1. Pass a valid non-null execution ID string (a 32-char Flowable UUID, e.g. from task.getExecutionId())
2. Check the ID for null before calling executionId() and take an alternate code path when absent
3. Fix the upstream lookup that produced the null ID (entity not found or not refreshed)
4. For broader searches, drop the executionId() restriction and filter by other criteria instead

Example fix

// before
Execution execution = runtimeService.createExecutionQuery().executionId(task.getExecutionId()).singleResult(); // throws if null
// after
String execId = task.getExecutionId();
Execution execution = execId != null
    ? runtimeService.createExecutionQuery().executionId(execId).singleResult()
    : null;

Objects.requireNonNull(executionId, "executionId must not be null before querying");
query.executionId(executionId);

boolean hasExecutionId(Task t) { return t != null && t.getExecutionId() != null; }

try {
    query.executionId(executionId);
} catch (org.flowable.common.engine.api.FlowableIllegalArgumentException e) {
    throw new IllegalStateException("Cannot query execution: no execution id available", e);
}

When it happens

Trigger: Calling executionQuery.executionId(null), commonly when the execution ID variable was never populated or was returned null from a previous lookup (e.g. task.getExecutionId() on a detached entity).

Common situations: A prior Task/Execution lookup returned null and its ID was propagated; deserialized DTOs with missing id fields; REST path parameters parsed to null.

Related errors

• before time is null
• Business key is null
• Candidate group is null
• Candidate group list is null
• Candidate user is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/b15a941af16c552c. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-engine/src/main/java/org/flowable/engine/impl/ExecutionQueryImpl.java:470

    }
    
    @Override
    public ExecutionQuery excludeProcessDefinitionKeys(Set<String> excludeProcessDefinitionKeys) {
        if (excludeProcessDefinitionKeys == null) {
            throw new FlowableIllegalArgumentException("Process definition keys is null");
        }
        if (inOrStatement) {
            this.currentOrQueryObject.excludeProcessDefinitionKeys = excludeProcessDefinitionKeys;
        } else {
            this.excludeProcessDefinitionKeys = excludeProcessDefinitionKeys;
        }
        return this;
    }

    @Override
    public ExecutionQueryImpl executionId(String executionId) {
        if (executionId == null) {
            throw new FlowableIllegalArgumentException("Execution id is null");
        }
        if (inOrStatement) {
            this.currentOrQueryObject.executionId = executionId;
        } else {
            this.executionId = executionId;
        }
        return this;
    }

    @Override
    public ExecutionQueryImpl activityId(String activityId) {
        if (inOrStatement) {
            this.currentOrQueryObject.activityId = activityId;
            if (activityId != null) {
                this.currentOrQueryObject.isActive = true;
            }
            
        } else {

View on GitHub (pinned to d6d39ce1c6)