private Collection<List<WorkflowTask>> children() {
        Collection<List<WorkflowTask>> workflowTaskLists = new LinkedList<>();

        switch (TaskType.of(type)) {
            case DECISION:
            case SWITCH:
                workflowTaskLists.addAll(decisionCases.values());
                workflowTaskLists.add(defaultCase);
                break;
            case FORK_JOIN:
                workflowTaskLists.addAll(forkTasks);
                break;
            case DO_WHILE:
                workflowTaskLists.add(loopOver);
                break;
            default:
                break;
        }
        return workflowTaskLists;
    }
@param expression the expression to set
common/src/main/java/com/netflix/conductor/common/metadata/workflow/WorkflowTask.java