code: @Override
      String execute(final Task task) {
          if (Config.DEBUG) {
              Log.v(TAG, "execute() task=" + task);
          }
          checkExecutor();
          assert task != null;
          final ITaskRunnable runnable = TaskFactory.createRunnable(task);
          final String group = task.getGroup();
          final String name = task.getName();
          addToRunnableMap(name, runnable);
          addToGroupMap(name, group);
  
          runnable.setFuture(mExecutor.submit(runnable));
          return name;
      }
docs: 执行异步任务
  
  @param task 任务对象
  @return 返回内部生成的此次任务的TAG