Python_递归锁

递归锁能够保证线程之间改变变量的独立性，
多个线程共同修改一个变量时一定要加上递归锁

# Author : Xuefeng

# 导入必要的模块
import threading,time


def run1():
    '''
    定义第一个程序来创建一个修改参数的线程
    :return: 
    '''
    print("Grab the first part data.")
    lock.acquire()
    global num
    num += 1
    lock.release()
    return num

def run2():
    '''
    定义第二个程序来创建一个修改参数的线程
    :return: 
    '''
    print("Grab the second part data.")
    lock.acquire()
    global num2
    num2 += 1
    lock.release()
    return num2

def run3():
    '''
    定义第三个程序来创建一个修改参数的线程
    :return: 
    '''
    lock.acquire()
    res = run1()
    print("----------Between run1 and run2------------- ")
    res2 = run2()
    print(res, res2)
    lock.release()

# 初始化主线程中的变量
num, num2 = 0, 0
# 实例化递归锁
lock = threading.RLock()
# 循环创建线程改变参数
for i in range(9):
    t = threading.Thread(target=run3)
    t.start()

# 判断线程是否都执行结束
while threading.active_count() != 1:
    print(threading.active_count())
else:
    print("--------All threads done--------")
    print(num, num2)