code: public TaskBuilder<Result> action(final Callable<Result> action) {
          if (action instanceof TaskCallable) {
              this.action = (TaskCallable<Result>) action;
          } else {
              this.action = new WrappedCallable<Result>(action);
          }
          return this;
      }
docs: 设置需要执行的任务
  
  @param action Callable
  @return TaskBuilder