多线程

多线程 threading
1、观察线程

import threading
def thread_job():
print(threading.current_thread())
def main():
print(threading.active_count())#打印threading的数目
print(threading.enumerate())#当前线程名字
print(threading.current_thread())#当前线程名字
add_threading=threading.Thread(target=thread_job)
add_threading.start()#开始
if __name__ == "__main__":
main()

2、jion线程同步

import threading
import time
def thread_job():
print("T1 START\n")
time.sleep(0.2)
print(threading.current_thread())
def main():
add_threading=threading.Thread(target=thread_job,name="T1")
add_threading.start()
add_threading.join()
print("all done")
if __name__ == "__main__":
main()

3、queue线程队列

import threading
import time
from queue import Queue
def job(l,q):
print(threading.enumerate())#当前线程名字
time.sleep(1)
for i in range(len(l)):
l[i]=l[i]**2
q.put(l)
def multithreading():
q=Queue()
threads=[]
data=[[1,2,34,5,6,7,8,9,0,11,13],[2,4],[4,5,6],[5,6,7,8,9,0]]
for i in range(4):
t=threading.Thread(target=job,args=(data[i],q))
t.start()
threads.append(t)
for thread in threads:
thread.join()
results=[]
for _ in range(4):
results.append(q.get())
print(results)
if __name__ == "__main__":
multithreading()

4、线程锁lock

import threading
import time
def job1():
global a,lock
lock.acquire()
for i in range(10):
a=a+10
print("job1",a)
lock.release()

def job2():
global a,lock
lock.acquire()
for i in range(10):
a=a+50
print("job2",a)
lock.release()

if __name__ == "__main__":
lock=threading.Lock()
a=0
t1=threading.Thread(target=job1,name="job1")
t2=threading.Thread(target=job2,name="job2")
t1.start()
t2.start()
t1.join()
t2.join()
print("result")