本文實例講述了Python設計模式之抽象工廠模式原理與用法。分享給大家供大家參考，具體如下：

抽象工廠模式(Abstract Factory Pattern):提供一個創(chuàng)建一系列相關或相互依賴對象的接口，而無需指定它們的類

下面是一個抽象工廠的demo：

#!/usr/bin/env python# -*- coding:utf-8 -*-__author__ = 'Andy'"""大話設計模式設計模式——抽象工廠模式抽象工廠模式(Abstract Factory Pattern):提供一個創(chuàng)建一系列相關或相互依賴對象的接口，而無需指定它們的類"""import sys#抽象用戶表類class User(object):  def get_user(self):    pass  def insert_user(self):    pass#抽象部門表類class Department(object):  def get_department(self):    pass  def insert_department(self):    pass#操作具體User數(shù)據(jù)庫類-Mysqlclass MysqlUser(User):  def get_user(self):    print 'MysqlUser get User'  def insert_user(self):    print 'MysqlUser insert User'#操作具體Department數(shù)據(jù)庫類-Mysqlclass MysqlDepartment(Department):  def get_department(self):    print 'MysqlDepartment get department'  def insert_department(self):    print 'MysqlDepartment insert department'#操作具體User數(shù)據(jù)庫-Orcalclass OrcaleUser(User):  def get_user(self):    print 'OrcalUser get User'  def insert_user(self):    print 'OrcalUser insert User'#操作具體Department數(shù)據(jù)庫類-Orcalclass OrcaleDepartment(Department):  def get_department(self):    print 'OrcalDepartment get department'  def insert_department(self):    print 'OrcalDepartment insert department'#抽象工廠類class AbstractFactory(object):  def create_user(self):    pass  def create_department(self):    passclass MysqlFactory(AbstractFactory):  def create_user(self):    return MysqlUser()  def create_department(self):    return MysqlDepartment()class OrcaleFactory(AbstractFactory):  def create_user(self):    return OrcaleUser()  def create_department(self):    return OrcaleDepartment()if __name__ == "__main__":  db = sys.argv[1]  myfactory = ''  if db == 'Mysql':    myfactory = MysqlFactory()  elif db == 'Orcal':    myfactory = OrcaleFactory()  else:    print "不支持的數(shù)據(jù)庫類型"    exit(0)  user = myfactory.create_user()  department = myfactory.create_department()  user.insert_user()  user.get_user()  department.insert_department()  department.get_department()

上面類的設計如下圖：

優(yōu)點：

具體工廠類如MysqlFactory在一個應用中只需要初始化一次，這樣改動一個具體工廠變得很容易，只需要改變具體工廠就可以改變整個產(chǎn)品的配置。

具體的創(chuàng)建實例過程與客戶端分離，客戶端通過他們的抽象接口操縱實例，產(chǎn)品的具體類名也被具體工廠的實現(xiàn)分離，不會出現(xiàn)在客戶端代碼中

缺點：在新增一個具體工廠就需要增加多個類才能實現(xiàn)