Python3备份

发布时间:2019-10-16 17:30:20编辑:auto阅读(577)

    Python3生产者/消费者模式

    import threading  
    import queue,time,random  
      
    class Goods:#产品类  
        def __init__(self):  
            self.count = 0
        def add(self,num = 1):
            self.count += num  
        def sub(self):  
            if self.count>=0:  
                self.count -= 1  
        def empty(self):  
            return self.count <= 0
    
    class Producer(threading.Thread):#生产者类  
        def __init__(self,condition,goods,sleeptime = 1):#sleeptime=1  
            threading.Thread.__init__(self)  
            self.cond = condition  
            self.goods = goods  
            self.sleeptime = sleeptime  
        def run(self):  
            cond = self.cond  
            goods = self.goods  
            while True:
                cond.acquire()#锁住资源  
                goods.add()
                print("产品数量:",goods.count,"生产者线程")
                cond.notifyAll()#唤醒所有等待的线程--》其实就是唤醒消费者进程 
                cond.release()#解锁资源
                time.sleep(self.sleeptime)
    
    class Consumer(threading.Thread):#消费者类  
        def __init__(self,condition,goods,sleeptime = 2):#sleeptime=2  
            threading.Thread.__init__(self)
            self.cond = condition
            self.goods = goods
            self.sleeptime = sleeptime
        def run(self):  
            cond = self.cond
            goods = self.goods
            while True:
                time.sleep(self.sleeptime)
                cond.acquire()#锁住资源
                while goods.empty():#如无产品则让线程等待
                    cond.wait()
                goods.sub()
                print("产品数量:",goods.count,"消费者线程")
                cond.release()#解锁资源  
    
    g = Goods()
    c = threading.Condition()
      
    pro = Producer(c,g)  
    pro.start()  
      
    con = Consumer(c,g)  
    con.start()  
    

    Python的锁

    import threading
    import time
    
    private_lock = threading.RLock()
    num = 0
    
    
    class MyThread(threading.Thread):
        def __init__(self, name):
            threading.Thread.__init__(self)
            self.t_name = name 
            
        def run(self):
            global num
            while True:
                private_lock.acquire()
                if num > 4:
                    print("%s" % self.t_name)
                    time.sleep(5)
                    private_lock.release()
                    break
                num += 1
                private_lock.release()
    
    
    def test1():
        thread1 = MyThread('A')
        thread2 = MyThread('B')
        thread1.start()
        thread2.start()
    
    
    if __name__ == '__main__':
        test1()
    

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