Python编程：设计模式之单例和简单工厂

# 1、Python与设计模式--单例模式
# https://yq.aliyun.com/articles/70418
import threading
import time
# 抽象单例
class Singleton(object):
    def __new__(cls, *args, **kwargs):
        if not hasattr(cls, "_instance"):
            cls._instance = super(Singleton, cls).__new__(cls, *args, **kwargs)
        return cls._instance
# 总线
class Bus(Singleton):
    lock = threading.RLock() 
    def sendData(self, data):
        Bus.lock.acquire()
        time.sleep(3)
        print("sendData:", data)
        Bus.lock.release()
# 线程对象
class VisitEntity(threading.Thread):
    my_bus = ""
    name = ""
    def getName(self):
        return name
    def setName(self, name):
        self.name = name
    def run(self):
        self.my_bus = Bus()
        self.my_bus.sendData(self.name)
if __name__ == '__main__':
    for i in range(3):
        print("run %s"%(i))
        my_entity = VisitEntity()
        my_entity.setName("entity_" + str(i))
        my_entity.start()
"""
run 0
run 1
run 2
sendData: entity_0
sendData: entity_1
sendData: entity_2
"""
# 关于super   http://python.jobbole.com/86787/

# 设计模式之简单工厂模式
# http://mp.weixin.qq.com/s/3J0hq3I95iKnbT5YjniZVQ
"""
简单工厂模式: 
专门定义一个 工厂类 来负责创建 产品类 的实例，被创建的产品通常都具有共同的父类。
三个角色:
简单工厂（SimpleProductFactory）角色
抽象产品（Product）角色
具体产品（Concrete Product）角色
"""
# 抽象产品
class Fruit(object):
    def produce(self):
        print("Fruit is prodeced")
# 具体产品
class Apple(Fruit):
    def produce(self):
        print("Apple is produced")
class Banana(Fruit):
    def produce(self):
        print("Banana is produced")
# 简单工厂
class Factory(object):
    def produceFruit(self, fruit_name):
        if fruit_name == "apple":
            return Apple()
        elif fruit_name == "banana":
            return Banana()
        else:
            return Fruit()
if __name__ == '__main__':
    factory = Factory()
    apple = factory.produceFruit("apple")
    apple.produce()
    banana = factory.produceFruit("banana")
    banana.produce()
    fruit = factory.produceFruit("fruit")
    fruit.produce()
"""
Apple is produced
Banana is produced
Fruit is prodeced
"""