@ApiMethod(name = "storeTask")
 public void storeTask(TaskBean taskBean) {
   DatastoreService datastoreService = DatastoreServiceFactory.getDatastoreService();
   Transaction txn = datastoreService.beginTransaction();
   try {
     Key taskBeanParentKey = KeyFactory.createKey("TaskBeanParent", "todo.txt");
     Entity taskEntity = new Entity("TaskBean", taskBean.getId(), taskBeanParentKey);
     taskEntity.setProperty("data", taskBean.getData());
     datastoreService.put(taskEntity);
     txn.commit();
   } finally {
     if (txn.isActive()) {
       txn.rollback();
     }
   }
 }