flowable/flowable-engine · error · FlowableIllegalArgumentException

callback id is null

Error message

callback id is null

What it means

HistoricCaseInstanceQueryImpl.caseInstanceCallbackId(String) filters case instances by their callback identifier. A null callbackId cannot form a valid query condition, so the engine throws FlowableIllegalArgumentException during query construction. Deliberate fail-fast validation in the public API.

Solutions

1. Pass a valid non-null callback id string to caseInstanceCallbackId().
2. If the callback id is optional, guard the call and only apply the filter when present.
3. Validate the upstream payload/config so the callback id is never null by the time the query is built.
4. Catch FlowableIllegalArgumentException for external input and return a validation error to the caller.

Example fix

// before
query.caseInstanceCallbackId(payload.getCallbackId()); // may be null

// after
if (payload.getCallbackId() != null) {
    query.caseInstanceCallbackId(payload.getCallbackId());
}

if (callbackId != null && !callbackId.isEmpty()) {
    query.caseInstanceCallbackId(callbackId);
}

boolean hasCallbackId = c -> c != null && !c.trim().isEmpty();

try {
    query.caseInstanceCallbackId(callbackId);
} catch (FlowableIllegalArgumentException e) {
    throw new IllegalArgumentException("Invalid callback id filter: " + e.getMessage());
}

When it happens

Trigger: Calling historicCaseInstanceQuery.caseInstanceCallbackId(null), usually when the callback id variable comes from an external system payload or config that was not set.

Common situations: Processing inbound integration messages where the callbackId field is missing; configuration migrations dropping the callback property; lookups by correlation id when the id was never registered.

Related errors

• callbackId is null
• case definition tenantId is null
• caseDefinition tenantId is null
• Parent id is null
• Provided sub scope id is null

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/0d4ddc81e8c77b29. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-cmmn-engine/src/main/java/org/flowable/cmmn/engine/impl/history/HistoricCaseInstanceQueryImpl.java:731

    @Override
    public HistoricCaseInstanceQuery lastReactivatedBy(String userId) {
        if (userId == null) {
            throw new FlowableIllegalArgumentException("user id is null");
        }
        if (inOrStatement) {
            this.currentOrQueryObject.lastReactivatedBy = userId;
        } else {
            this.lastReactivatedBy = userId;
        }

        return this;
    }

    @Override
    public HistoricCaseInstanceQuery caseInstanceCallbackId(String callbackId) {
        if (callbackId == null) {
            throw new FlowableIllegalArgumentException("callback id is null");
        }
        if (inOrStatement) {
            this.currentOrQueryObject.callbackId = callbackId;
        } else {
            this.callbackId = callbackId;
        }
        return this;
    }

    @Override
    public HistoricCaseInstanceQuery caseInstanceCallbackIds(Set<String> callbackIds) {
        if (callbackIds == null || callbackIds.isEmpty()) {
            throw new FlowableIllegalArgumentException("callbackIds is null or empty");
        }
        if (inOrStatement) {
            this.currentOrQueryObject.callbackIds = callbackIds;
        } else {
            this.callbackIds = callbackIds;

View on GitHub (pinned to d6d39ce1c6)