#创建线程
#encoding=utf-8 from threading import Thread #引入线程的包 import time def run(a = None, b = None) : print(a, b ) time.sleep(1) t = Thread(name = "g1",target = run, args = ("g1", "thread")) #此时线程是新建状态 print(t.getName()) #获得线程对象名称 print(t.isAlive()) #判断线程是否还活着，在start后，在执行完毕前调用isAlive()才会返回True t.start() #启动线程 t.join() #主线程等待子线程t执行结束 print("Done!")
D:>py -3 a.py
g1
False
g1 thread
Done!
#通过继承Thread类创建线程
#encoding=utf-8 import threading import time class timer(threading.Thread): #The timer class is derived from the class threading.Thread def __init__(self, num, interval): threading.Thread.__init__(self) self.thread_num = num self.interval = interval self.thread_stop = False def run(self): #Overwrite run() method, put what you want the thread do here while not self.thread_stop: print('Thread Object(%d), Time:%s ' %(self.thread_num, time.ctime()) ) time.sleep(self.interval) def stop(self): self.thread_stop = True def test(): thread1 = timer(1, 1) thread2 = timer(2, 2) thread1.start() #执行类里面的run方法 thread2.start() time.sleep(10) thread1.stop() thread2.stop() #停止线程 if __name__ == '__main__': test()
D:>py -3 a.py
Thread Object(1), Time:Fri Nov 8 22:35:12 2019
Thread Object(2), Time:Fri Nov 8 22:35:12 2019
Thread Object(1), Time:Fri Nov 8 22:35:13 2019
Thread Object(2), Time:Fri Nov 8 22:35:14 2019
Thread Object(1), Time:Fri Nov 8 22:35:14 2019
Thread Object(1), Time:Fri Nov 8 22:35:15 2019
Thread Object(2), Time:Fri Nov 8 22:35:16 2019
Thread Object(1), Time:Fri Nov 8 22:35:16 2019
Thread Object(1), Time:Fri Nov 8 22:35:17 2019
Thread Object(2), Time:Fri Nov 8 22:35:18 2019
Thread Object(1), Time:Fri Nov 8 22:35:18 2019
Thread Object(1), Time:Fri Nov 8 22:35:19 2019
Thread Object(2), Time:Fri Nov 8 22:35:20 2019
Thread Object(1), Time:Fri Nov 8 22:35:20 2019
Thread Object(1), Time:Fri Nov 8 22:35:21 2019
#守护线程
# encoding: UTF-8 import threading import time class MyThread(threading.Thread): def __init__(self, id): threading.Thread.__init__(self) def run(self): time.sleep(5) print("This is " + self.getName()) if __name__ == "__main__": t1 = MyThread(999) #t1.setDaemon(True) # 将子线程设置为守护线程 t1.start() print("I am the father thread.") D:>py -3 a.py I am the father thread. This is Thread-1 #线程池 #encoding=utf-8 import time from multiprocessing.dummy import Pool as ThreadPool #ThreadPool表示给线程池取一个别名ThreadPool def run(fn): time.sleep(2) print(fn,end="") if __name__ == '__main__': testFL = [1,2,3,4,5] pool = ThreadPool(10)#创建10个容量的线程池并发执行 pool.map(run, testFL) pool.close() pool.join()
D:>py -3 a.py
54321
线程锁
#encoding=utf-8 import time from multiprocessing.dummy import Pool as ThreadPool #ThreadPool表示给线程池取一个别名ThreadPool def run(fn): time.sleep(2) print(fn,end="") if __name__ == '__main__': testFL = [1,2,3,4,5] pool = ThreadPool(10)#创建10个容量的线程池并发执行 pool.map(run, testFL) pool.close() pool.join()
#生产者和消费者
#encoding=utf-8 import threading import time data = 0 lock = threading.Lock()#创建一个锁对象 def func() : global data print("%s acquire lock... " %threading.currentThread().getName()) if lock.acquire() : print("%s get lock... " %threading.currentThread().getName()) data += 1 #must lock time.sleep(2)#其它操作 print("%s release lock... " %threading.currentThread().getName()) #调用release()将释放锁 lock.release() startTime = time.time() t1 = threading.Thread(target = func) t2 = threading.Thread(target = func) t3 = threading.Thread(target = func) t1.start() t2.start() t3.start() t1.join() t2.join() t3.join() endTime = time.time() print("used time is", endTime - startTime)
D:>py -3 a.py
Thread-1 acquire lock...
Thread-2 acquire lock...
Thread-1 get lock...
Thread-3 acquire lock...
Thread-1 release lock...
Thread-2 get lock...
Thread-2 release lock...
Thread-3 get lock...
Thread-3 release lock...
used time is 6.0552496910095215
>>> q.empty()
True
>>> q.full()
False
>>> q.qsize
<bound method Queue.qsize of <queue.Queue object at 0x0000000002551470>>
>>> q.qsize()
0
>>> q.get_nowait()
#死锁
#coding=utf-8 import threading import time lock1 = threading.Lock() lock2 = threading.Lock() print(lock1, lock2) class T1(threading.Thread): def __init__(self, name): threading.Thread.__init__(self) self.t_name = name def run(self): lock1.acquire() time.sleep(1)#睡眠的目的是让线程2获得调度，得到第二把锁 print('in thread T1',self.t_name) time.sleep(2) lock2.acquire() #线程1请求第二把锁 print('in lock l2 of T1') lock2.release() lock1.release() class T2(threading.Thread): def __init__(self, name): threading.Thread.__init__(self) self.t_name = name def run(self): lock2.acquire() time.sleep(2)#睡眠的目的是让线程1获得调度，得到第一把锁 print('in thread T2',self.t_name) lock1.acquire() #线程2请求第一把锁 print('in lock l1 of T2') lock1.release() lock2.release() def test(): thread1 = T1('A') thread2 = T2('B') thread1.start() thread2.start() if __name__== '__main__': test()
D:>py -3 a.py
<unlocked _thread.lock object at 0x0000023760EA8B98> <unlocked _thread.lock object at 0x0000023760EA8C38>
in thread T1 A
in thread T2 B
t2：拿到了lock2锁，等lock1锁
t1：拿到了lock1锁，等lock2锁
协程
协程：一个线程里的多个任务
#yield实现协程
import time def consumer(name): #生成器 print("%s 要开始吃包子了！"%(name)) while True: baozi=yield #暂停，记录位置，返回跳出（接收下面send发送的数据，接收到数据后才会继续执行） print("包子%s，%s吃了"%(baozi,name)) def producer(name): c=consumer("消费者") #只是变成一个生成器 c.__next__() #next只唤醒yield不传递值 for i in range(4): #暂停 time.sleep(1) print("%s 做了包子%s"%(name,i)) c.send(i) #发送数据 if __name__=="__main__": producer("生产者") from greenlet import greenlet def proc1(): #任务1 print(12) gr2.switch() print(34) gr2.switch() def proc2(): #任务2 print(56) gr1.switch() #切换 print(78) if __name__=="__main__": gr1=greenlet(proc1) #启动一个协程 gr2=greenlet(proc2) gr1.switch() #先执行gr1指定运行的函数，然后在切换到gr2