flowable/flowable-engine · error · FlowableException

To use the case service task a CaseInstanceService implement

Error message

To use the case service task a CaseInstanceService implementation needs to be available in the process engine configuration

What it means

The CMMN case service task (CaseTaskActivityBehavior) starts a case instance through the CaseInstanceService obtained from the process engine configuration. If no CaseInstanceService implementation is registered (typically because the flowable-cmmn engine/converter isn't wired into the process engine configuration), the behavior cannot proceed and throws this FlowableException.

Source

Thrown at modules/flowable-engine/src/main/java/org/flowable/engine/impl/bpmn/behavior/CaseTaskActivityBehavior.java:69

    private static final Logger LOGGER = LoggerFactory.getLogger(CaseTaskActivityBehavior.class);

    private static final long serialVersionUID = 1L;

    @Override
    public void execute(DelegateExecution execution) {

        ExecutionEntity executionEntity = (ExecutionEntity) execution;
        CaseServiceTask caseServiceTask = (CaseServiceTask) executionEntity.getCurrentFlowElement();

        CommandContext commandContext = CommandContextUtil.getCommandContext();

        ProcessEngineConfigurationImpl processEngineConfiguration = CommandContextUtil.getProcessEngineConfiguration(commandContext);
        ExecutionEntityManager executionEntityManager = CommandContextUtil.getExecutionEntityManager(commandContext);
        ExpressionManager expressionManager = processEngineConfiguration.getExpressionManager();
        CaseInstanceService caseInstanceService = processEngineConfiguration.getCaseInstanceService();
        
        if (caseInstanceService == null) {
            throw new FlowableException("To use the case service task a CaseInstanceService implementation needs to be available in the process engine configuration");
        }

        String businessKey = null;
        if (!StringUtils.isEmpty(caseServiceTask.getBusinessKey())) {
            Expression expression = expressionManager.createExpression(caseServiceTask.getBusinessKey());
            businessKey = expression.getValue(execution).toString();

        } else if (caseServiceTask.isInheritBusinessKey()) {
            ExecutionEntity processInstance = executionEntityManager.findById(execution.getProcessInstanceId());
            businessKey = processInstance.getBusinessKey();
        }
        
        String caseInstanceName = null;
        if (StringUtils.isNotEmpty(caseServiceTask.getCaseInstanceName())) {
            Expression caseInstanceNameExpression = expressionManager.createExpression(caseServiceTask.getCaseInstanceName());
            caseInstanceName = caseInstanceNameExpression.getValue(execution).toString();
        }
        

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Add the flowable-cmmn-engine dependency and run via CmmnEngineConfiguration (or app engine) so the CaseInstanceService is registered automatically.
2. Explicitly set an implementation: processEngineConfiguration.setCaseInstanceService(new DefaultCaseInstanceService(...)) if wiring engines manually.
3. If cases are not intended, replace the case service task in the BPMN with a call activity or service task.
4. Verify engine initialization order so the process engine is built after the CMMN engine registers its service.

Example fix

// before: plain process engine without cmmn
ProcessEngineConfiguration.createStandaloneProcessEngineConfiguration()...
// after: use the combined configuration so CaseInstanceService is available
CmmnEngineConfiguration.createStandaloneCmmnEngineConfiguration()... // or add flowable-cmmn-engine dependency

if (processEngineConfiguration.getCaseInstanceService() == null) {
    throw new IllegalStateException("Case service task used but CaseInstanceService not configured — add flowable-cmmn-engine");
}

try { runtimeService.startProcessInstanceByKey("procWithCaseTask"); }
catch (FlowableException e) { if (e.getMessage().contains("CaseInstanceService")) { enableCmmnIntegration(); } else { throw e; } }

When it happens

Trigger: A process containing a case service task (flowable:type="case") executes while processEngineConfiguration.getCaseInstanceService() returns null — i.e. the engine was built without CMMN integration.

Common situations: Using ProcessEngineConfiguration standalone without flowable-cmmn-engine on the classpath; custom engine configuration that doesn't install the CMMN CaseInstanceService (e.g. missing cmmnEngineConfiguration/engines wiring); case task introduced into a BPMN-only deployment.

Understand the failure class

Background: "not installed", "pip install", "required for": how missing-dependency errors surface across open-source libraries — this error's family across 34 libraries.

Related errors

• Form engine is not initialized
• Could not execute decision instance: no dmn service found. F
• Could not start process instance: no
• Form engine is not initialized
• DMN repository service is not available

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/77b64450686431fe. Report an issue: GitHub.