flowable/flowable-engine · error · FlowableObjectNotFoundException

No task found for taskId '

Error message

No task found for taskId '

What it means

GetTaskFormCmd builds the TaskFormData for a task. It first loads the TaskEntity by taskId; if TaskService returns null it throws FlowableObjectNotFoundException("No task found for taskId '<id>'", Task.class), i.e. the id is syntactically fine but no such task exists.

Source

Thrown at modules/flowable-engine/src/main/java/org/flowable/engine/impl/cmd/GetTaskFormCmd.java:50

/**
 * @author Tom Baeyens
 * @author Joram Barrez
 */
public class GetTaskFormCmd implements Command<TaskFormData>, Serializable {

    private static final long serialVersionUID = 1L;
    protected String taskId;

    public GetTaskFormCmd(String taskId) {
        this.taskId = taskId;
    }

    @Override
    public TaskFormData execute(CommandContext commandContext) {
        ProcessEngineConfigurationImpl processEngineConfiguration = CommandContextUtil.getProcessEngineConfiguration(commandContext);
        TaskEntity task = processEngineConfiguration.getTaskServiceConfiguration().getTaskService().getTask(taskId);
        if (task == null) {
            throw new FlowableObjectNotFoundException("No task found for taskId '" + taskId + "'", Task.class);
        }
        
        if (task.getProcessDefinitionId() != null && Flowable5Util.isFlowable5ProcessDefinitionId(commandContext, task.getProcessDefinitionId())) {
            Flowable5CompatibilityHandler compatibilityHandler = Flowable5Util.getFlowable5CompatibilityHandler();
            return compatibilityHandler.getTaskFormData(taskId);
        }

        FormHandlerHelper formHandlerHelper = processEngineConfiguration.getFormHandlerHelper();
        TaskFormHandler taskFormHandler = formHandlerHelper.getTaskFormHandlder(task);
        if (taskFormHandler == null) {
            throw new FlowableException("No taskFormHandler specified for '" + task + "'");
        }

        return taskFormHandler.createTaskForm(task);
    }

}

View on GitHub (pinned to d6d39ce1c6)

Solutions

1. Verify the task exists via taskService.createTaskQuery().taskId(taskId).singleResult() before requesting its form
2. Catch FlowableObjectNotFoundException and redirect the user to a task list / 'task no longer available' page
3. Confirm you are querying the same engine/database that owns the task
4. Check history cleanup policies if tasks are purged shortly after completion

Example fix

// before
TaskFormData form = taskService.getTaskForm(taskId); // throws if gone
// after
if (taskService.createTaskQuery().taskId(taskId).count() > 0) {
    TaskFormData form = taskService.getTaskForm(taskId);
}

boolean exists = taskService.createTaskQuery().taskId(taskId).count() > 0;

boolean taskExists(String taskId) {
    return taskId != null
        && taskService.createTaskQuery().taskId(taskId).count() > 0;
}

try {
    TaskFormData form = taskService.getTaskForm(taskId);
} catch (FlowableObjectNotFoundException e) {
    // task gone; redirect user to task list
    form = null;
}

When it happens

Trigger: Calling taskService.getTaskForm(taskId) with an unknown, deleted, or wrong-environment taskId.

Common situations: Form rendered from a stale/deep link after the task was completed and purged; ids copied between dev/test databases; multi-tenant setup querying the wrong engine.

Understand the failure class

Background: "Not found" and "does not exist" errors: why "Task not found", "No such folder", and "Can't find" fire when a lookup comes back empty — this error's family across 14 libraries.

Related errors

• task
• task
• Cannot resume task with id '
• Cannot find task with id ${taskId}
• case instance doesn't exist

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/3a2dcbcde23c2d99. Report an issue: GitHub.