add _thread module demo.

Author: yanbober

ConcurrentSpider/__init__.py

@@ -0,0 +1,32 @@
+import _thread
+import time
+'''
+Python 3.X _thread 模块演示 Demo
+当注释掉 self.lock.acquire() 和 self.lock.release() 后运行代码会发现最后的 count 为 467195 等，并发问题。
+当保留 self.lock.acquire() 和 self.lock.release() 后运行代码会发现最后的 count 为 1000000，锁机制保证了并发。
+time.sleep(5) 就是为了解决 _thread 模块的诟病，注释掉的话子线程没机会执行了
+'''
+class ThreadTest(object):
+    def __init__(self):
+        self.count = 0
+        self.lock = None
+
+    def runnable(self):
+        self.lock.acquire()
+        print('thread ident is '+str(_thread.get_ident())+', lock acquired!')
+        for i in range(0, 100000):
+            self.count += 1
+        print('thread ident is ' + str(_thread.get_ident()) + ', pre lock release!')
+        self.lock.release()
+
+    def test(self):
+        self.lock = _thread.allocate_lock()
+        for i in range(0, 10):
+            _thread.start_new_thread(self.runnable, ())
+
+if __name__ == '__main__':
+    test = ThreadTest()
+    test.test()
+    print('thread is running...')
+    time.sleep(5)
+    print('test finish, count is:' + str(test.count))