多线程编程中如果使用Condition对象代替lock, 能够实现在某个事件触发后才处理数据, condition中含有的方法:
- wait:线程挂起,收到notify通知后继续运行
- notify:通知其他线程, 解除其它线程的wai状态
- notifyAll(): 通知所有线程
- acquire和release: 获得锁和解除锁, 与lock类似,
- enter和exit使得对象支持上下文操作:
def __enter__(self):return self._lock.__enter__()def __exit__(self, *args):return self._lock.__exit__(*args)
代码:
import threadingfrom threading import Condition# conditionclass XiaoAi(threading.Thread):def __init__(self, cond):self.cond = condsuper().__init__(name="xiaoai")def run(self):self.cond.acquire()self.cond.wait()print('{}:ennn. '.format(self.name))self.cond.notify()self.cond.wait()print('{}:好嗒. '.format(self.name))self.cond.release()class TianMao(threading.Thread):def __init__(self, cond):super().__init__(name="tiaomao")self.cond = conddef run(self):self.cond.acquire()print('{}:hello ~ xiaoai. '.format(self.name))self.cond.notify()self.cond.wait()print('{}:我们来念一首诗吧! . '.format(self.name))self.cond.notify()self.cond.release()if __name__ == '__main__':condition = Condition()xiaoai = XiaoAi(condition)tianmao = TianMao(condition)# 启动顺序很重要xiaoai.start()tianmao.start()
打印结果:
tiaomao:hello ~ xiaoai.xiaoai:ennn.tiaomao:我们来念一首诗吧! .xiaoai:好嗒
总结:
这个比较鸡肋