class Operation:def GetResult(self):passclass OperationAdd(Operation): def GetResult(self): return self.op1+self.op2 class OperationSub(Operation): def GetResult(self): return self.op1-self.op2 class OperationMul(Operation): def GetResult(self): return self.op1*self.op2 class OperationDiv(Operation): def GetResult(self): try: result = self.op1/self.op2 return result except: print "error:divided by zero." return 0 class OperationUndef(Operation): def GetResult(self): print "Undefine operation." return 0 class OperationFactory: operation = {} operation["+"] = OperationAdd(); operation["-"] = OperationSub(); operation["*"] = OperationMul(); operation["/"] = OperationDiv(); def createOperation(self,ch): if ch in self.operation: op = self.operation[ch] else: op = OperationUndef() return op if __name__ == "__main__": op = raw_input("operator: ") opa = input("a: ") opb = input("b: ") factory = OperationFactory() cal = factory.createOperation(op) cal.op1 = opa cal.op2 = opb print cal.GetResult()

class CashSuper:def AcceptCash(self,money):return 0 class CashNormal(CashSuper): def AcceptCash(self,money): return money class CashRebate(CashSuper): discount = 0 def __init__(self,ds): self.discount = ds def AcceptCash(self,money): return money * self.discount class CashReturn(CashSuper): total = 0; ret = 0; def __init__(self,t,r): self.total = t self.ret = r def AcceptCash(self,money): if (money>=self.total): return money - self.ret else: return money class CashContext: def __init__(self,csuper): self.cs = csuper def GetResult(self,money): return self.cs.AcceptCash(money) if __name__ == "__main__": money = input("money:") strategy = {} strategy[1] = CashContext(CashNormal()) strategy[2] = CashContext(CashRebate(0.8)) strategy[3] = CashContext(CashReturn(300,100)) ctype = input("type:[1]for normal,[2]for 80% discount [3]for 300 -100.") if ctype in strategy: cc = strategy[ctype] else: print "Undefine type.Use normal mode." cc = strategy[1] print "you will pay:%d" %(cc.GetResult(money))

class Person:def __init__(self,tname):self.name = tname def Show(self): print "dressed %s" %(self.name) class Finery(Person): componet = None def __init__(self): pass def Decorate(self,ct): self.componet = ct def Show(self): if(self.componet!=None): self.componet.Show() class TShirts(Finery): def __init__(self): pass def Show(self): print "Big T-shirt " self.componet.Show() class BigTrouser(Finery): def __init__(self): pass def Show(self): print "Big Trouser " self.componet.Show() if __name__ == "__main__": p = Person("somebody") bt = BigTrouser() ts = TShirts() bt.Decorate(p) ts.Decorate(bt) ts.Show()

class Interface :def Request(self):return 0 class RealSubject(Interface): def Request(self): print "Real request." class Proxy(Interface): def Request(self): self.real = RealSubject() self.real.Request() if __name__ == "__main__": p = Proxy() p.Request()

class LeiFeng:def Sweep(self):print "LeiFeng sweep" class Student(LeiFeng): def Sweep(self): print "Student sweep" class Volenter(LeiFeng): def Sweep(self): print "Volenter sweep" class LeiFengFactory: def CreateLeiFeng(self): temp = LeiFeng() return temp class StudentFactory(LeiFengFactory): def CreateLeiFeng(self): temp = Student() return temp class VolenterFactory(LeiFengFactory): def CreateLeiFeng(self): temp = Volenter() return temp if __name__ == "__main__": sf = StudentFactory() s=sf.CreateLeiFeng() s.Sweep() sdf = VolenterFactory() sd=sdf.CreateLeiFeng() sd.Sweep()

import copy
class WorkExp:place="" year=0 class Resume: name = '' age = 0 def __init__(self,n): self.name = n def SetAge(self,a): self.age = a def SetWorkExp(self,p,y): self.place = p self.year = y def Display(self): print self.age print self.place print self.year def Clone(self): #实际不是“克隆”，只是返回了自身 return self if __name__ == "__main__": a = Resume("a") b = a.Clone() c = copy.copy(a) d = copy.deepcopy(a) a.SetAge(7) b.SetAge(12) c.SetAge(15) d.SetAge(18) a.SetWorkExp("PrimarySchool",1996) b.SetWorkExp("MidSchool",2001) c.SetWorkExp("HighSchool",2004) d.SetWorkExp("University",2007) a.Display() b.Display() c.Display() d.Display()

class TestPaper:def TestQuestion1(self):print "Test1:A. B. C. D." print "(%s)" %self.Answer1() def TestQuestion2(self): print "Test1:A. B. C. D." print "(%s)" %self.Answer2() def Answer1(self): return "" def Answer2(self): return "" class TestPaperA(TestPaper): def Answer1(self): return "B" def Answer2(self): return "C"; class TestPaperB(TestPaper): def Answer1(self): return "D" def Answer2(self): return "D"; if __name__ == "__main__": s1 = TestPaperA() s2 = TestPaperB() print "student 1" s1.TestQuestion1() s1.TestQuestion2() print "student 2" s2.TestQuestion1() s2.TestQuestion2()

class SubSystemOne:def MethodOne(self):print "SubSysOne" class SubSystemTwo: def MethodTwo(self): print "SubSysTwo" class SubSystemThree: def MethodThree(self): print "SubSysThree" class SubSystemFour: def MethodFour(self): print "SubSysFour" class Facade: def __init__(self): self.one = SubSystemOne() self.two = SubSystemTwo() self.three = SubSystemThree() self.four = SubSystemFour() def MethodA(self): print "MethodA" self.one.MethodOne() self.two.MethodTwo() self.four.MethodFour() def MethodB(self): print "MethodB" self.two.MethodTwo() self.three.MethodThree() if __name__ == "__main__": facade = Facade() facade.MethodA() facade.MethodB()

class Person:def CreateHead(self):passdef CreateHand(self): pass def CreateBody(self): pass def CreateFoot(self): pass class ThinPerson(Person): def CreateHead(self): print "thin head" def CreateHand(self): print "thin hand" def CreateBody(self): print "thin body" def CreateFoot(self): print "thin foot" class ThickPerson(Person): def CreateHead(self): print "thick head" def CreateHand(self): print "thick hand" def CreateBody(self): print "thick body" def CreateFoot(self): print "thick foot" class Director: def __init__(self,temp): self.p = temp def Create(self): self.p.CreateHead() self.p.CreateBody() self.p.CreateHand() self.p.CreateFoot() if __name__ == "__main__": p = ThickPerson() d = Director(p) d.Create()

class Observer:def __init__(self,strname,strsub):self.name = strname self.sub = strsub def Update(self): pass class StockObserver(Observer): #no need to rewrite __init__() def Update(self): print "%s:%s,stop watching Stock and go on work!" %(self.name,self.sub.action) class NBAObserver(Observer): def Update(self): print "%s:%s,stop watching NBA and go on work!" %(self.name,self.sub.action) class SecretaryBase: def __init__(self): self.observers = [] def Attach(self,new_observer): pass def Notify(self): pass class Secretary(SecretaryBase): def Attach(self,new_observer): self.observers.append(new_observer) def Notify(self): for p in self.observers: p.Update() if __name__ == "__main__": p = Secretary() s1 = StockObserver("xh",p) s2 = NBAObserver("wyt",p) p.Attach(s1); p.Attach(s2); p.action = "WARNING:BOSS "; p.Notify()

class IUser:def GetUser(self):passdef InsertUser(self): pass class IDepartment: def GetDepartment(self): pass def InsertDepartment(self): pass class CAccessUser(IUser): def GetUser(self): print "Access GetUser" def InsertUser(self): print "Access InsertUser" class CAccessDepartment(IDepartment): def GetDepartment(self): print "Access GetDepartment" def InsertDepartment(self): print "Access InsertDepartment" class CSqlUser(IUser): def GetUser(self): print "Sql GetUser" def InsertUser(self): print "Sql InsertUser" class CSqlDepartment(IDepartment): def GetDepartment(self): print "Sql GetDepartment" def InsertDepartment(self): print "Sql InsertDepartment" class IFactory: def CreateUser(self): pass def CreateDepartment(self): pass class AccessFactory(IFactory): def CreateUser(self): temp=CAccessUser() return temp def CreateDepartment(self): temp = CAccessDepartment() return temp class SqlFactory(IFactory): def CreateUser(self): temp = CSqlUser() return temp def CreateDepartment(self): temp = CSqlDepartment() return temp if __name__ == "__main__": factory = SqlFactory() user=factory.CreateUser() depart=factory.CreateDepartment() user.GetUser() depart.GetDepartment()

class State:def WirteProgram(self):passclass Work: def __init__(self): self.hour = 9 self.current = ForenoonState() def SetState(self,temp): self.current = temp def WriteProgram(self): self.current.WriteProgram(self) class NoonState(State): def WriteProgram(self,w): print "noon working" if (w.hour<13): print "fun." else: print "need to rest." class ForenoonState(State): def WriteProgram(self,w): if (w.hour<12): print "morning working" print "energetic" else: w.SetState(NoonState()) w.WriteProgram() if __name__ == "__main__": mywork = Work() mywork.hour = 9 mywork.WriteProgram() mywork.hour =14 mywork.WriteProgram()

class Target:def Request():print "common request." class Adaptee(Target): def SpecificRequest(self): print "specific request." class Adapter(Target): def __init__(self,ada): self.adaptee = ada def Request(self): self.adaptee.SpecificRequest() if __name__ == "__main__": adaptee = Adaptee() adapter = Adapter(adaptee) adapter.Request()

class Originator:def __init__(self):self.state = "" def Show(self): print self.state def CreateMemo(self): return Memo(self.state) def SetMemo(self,memo): self.state = memo.state class Memo: state= "" def __init__(self,ts): self.state = ts class Caretaker: memo = "" if __name__ == "__main__": on = Originator() on.state = "on" on.Show() c = Caretaker() c.memo=on.CreateMemo() on.state="off" on.Show() on.SetMemo(c.memo) on.Show()

class Component:def __init__(self,strName):self.m_strName = strName def Add(self,com): pass def Display(self,nDepth): pass class Leaf(Component): def Add(self,com): print "leaf can't add" def Display(self,nDepth): strtemp = "" for i in range(nDepth): strtemp=strtemp+"-" strtemp=strtemp+self.m_strName print strtemp class Composite(Component): def __init__(self,strName): self.m_strName = strName self.c = [] def Add(self,com): self.c.append(com) def Display(self,nDepth): strtemp="" for i in range(nDepth): strtemp=strtemp+"-" strtemp=strtemp+self.m_strName print strtemp for com in self.c: com.Display(nDepth+2) if __name__ == "__main__": p = Composite("Wong") p.Add(Leaf("Lee")) p.Add(Leaf("Zhao")) p1 = Composite("Wu") p1.Add(Leaf("San")) p.Add(p1) p.Display(1);

#-*- encoding=utf-8 -*-
print '----------------------方法1--------------------------' #方法1,实现__new__方法 #并在将一个类的实例绑定到类变量_instance上, #如果cls._instance为None说明该类还没有实例化过,实例化该类,并返回 #如果cls._instance不为None,直接返回cls._instance class Singleton(object): def __new__(cls, *args, **kw): if not hasattr(cls, '_instance'): orig = super(Singleton, cls) cls._instance = orig.__new__(cls, *args, **kw) return cls._instance class MyClass(Singleton): a = 1 one = MyClass() two = MyClass() two.a = 3 print one.a #3 #one和two完全相同,可以用id(), ==, is检测 print id(one) #29097904 print id(two) #29097904 print one == two #True print one is two #True print '----------------------方法2--------------------------' #方法2,共享属性;所谓单例就是所有引用(实例、对象)拥有相同的状态(属性)和行为(方法) #同一个类的所有实例天然拥有相同的行为(方法), #只需要保证同一个类的所有实例具有相同的状态(属性)即可 #所有实例共享属性的最简单最直接的方法就是__dict__属性指向(引用)同一个字典(dict) #可参看:http://code.activestate.com/recipes/66531/ class Borg(object): _state = {} def __new__(cls, *args, **kw): ob = super(Borg, cls).__new__(cls, *args, **kw) ob.__dict__ = cls._state return ob class MyClass2(Borg): a = 1 one = MyClass2() two = MyClass2() #one和two是两个不同的对象,id, ==, is对比结果可看出 two.a = 3 print one.a #3 print id(one) #28873680 print id(two) #28873712 print one == two #False print one is two #False #但是one和two具有相同的（同一个__dict__属性）,见: print id(one.__dict__) #30104000 print id(two.__dict__) #30104000 print '----------------------方法3--------------------------' #方法3:本质上是方法1的升级（或者说高级）版 #使用__metaclass__（元类）的高级python用法 class Singleton2(type): def __init__(cls, name, bases, dict): super(Singleton2, cls).__init__(name, bases, dict) cls._instance = None def __call__(cls, *args, **kw): if cls._instance is None: cls._instance = super(Singleton2, cls).__call__(*args, **kw) return cls._instance class MyClass3(object): __metaclass__ = Singleton2 one = MyClass3() two = MyClass3() two.a = 3 print one.a #3 print id(one) #31495472 print id(two) #31495472 print one == two #True print one is two #True print '----------------------方法4--------------------------' #方法4:也是方法1的升级（高级）版本, #使用装饰器(decorator), #这是一种更pythonic,更elegant的方法, #单例类本身根本不知道自己是单例的,因为他本身(自己的代码)并不是单例的 def singleton(cls, *args, **kw): instances = {} def _singleton(): if cls not in instances: instances[cls] = cls(*args, **kw) return instances[cls] return _singleton @singleton class MyClass4(object): a = 1 def __init__(self, x=0): self.x = x one = MyClass4() two = MyClass4() two.a = 3 print one.a #3 print id(one) #29660784 print id(two) #29660784 print one == two #True print one is two #True one.x = 1 print one.x #1 print two.x #1

class HandsetSoft(object):def Run(self):passclass HandsetGame(HandsetSoft): def Run(self): print "Game" class HandsetAddressList(HandsetSoft): def Run(self): print "Address List" class HandsetBrand(object): def __init__(self): self.m_soft = None def SetHandsetSoft(self,temp): self.m_soft= temp def Run(self): pass class HandsetBrandM(HandsetBrand): def Run(self): if not (self.m_soft == None): print "BrandM" self.m_soft.Run() class HandsetBrandN(HandsetBrand): def Run(self): if not (self.m_soft == None): print "BrandN" self.m_soft.Run() if __name__ == "__main__": brand = HandsetBrandM() brand.SetHandsetSoft(HandsetGame()) brand.Run() brand.SetHandsetSoft(HandsetAddressList()) brand.Run() 

class Barbucer:def MakeMutton(self):print "Mutton" def MakeChickenWing(self): print "Chicken Wing" class Command: def __init__(self,temp): self.receiver=temp def ExecuteCmd(self): pass class BakeMuttonCmd(Command): def ExecuteCmd(self): self.receiver.MakeMutton() class ChickenWingCmd(Command): def ExecuteCmd(self): self.receiver.MakeChickenWing() class Waiter: def __init__(self): self.order =[] def SetCmd(self,command): self.order.append(command) print "Add Order" def Notify(self): for cmd in self.order: #self.order.remove(cmd) #lead to a bug  cmd.ExecuteCmd() if __name__ == "__main__": barbucer=Barbucer() cmd=BakeMuttonCmd(barbucer) cmd2=ChickenWingCmd(barbucer) girl=Waiter() girl.SetCmd(cmd) girl.SetCmd(cmd2) girl.Notify()

c=[0,1,2,3]
for i in c:print i c.remove(i) #output: #0 #2

class Request:def __init__(self,tcontent,tnum):self.content = tcontent self.num = tnum class Manager: def __init__(self,temp): self.name = temp def SetSuccessor(self,temp): self.manager = temp def GetRequest(self,req): pass class CommonManager(Manager): def GetRequest(self,req): if(req.num>=0 and req.num<10): print "%s handled %d request." %(self.name,req.num) else: self.manager.GetRequest(req) class MajorDomo(Manager): def GetRequest(self,req): if(req.num>=10): print "%s handled %d request." %(self.name,req.num) if __name__ == "__main__": common = CommonManager("Zhang") major = MajorDomo("Lee") common.SetSuccessor(major) req = Request("rest",33) common.GetRequest(req) req2 = Request("salary",3) common.GetRequest(req2)

class Mediator:def Send(self,message,col):passclass Colleague: def __init__(self,temp): self.mediator = temp class Colleague1(Colleague): def Send(self,message): self.mediator.Send(message,self) def Notify(self,message): print "Colleague1 get a message:%s" %message class Colleague2(Colleague): def Send(self,message): self.mediator.Send(message,self) def Notify(self,message): print "Colleague2 get a message:%s" %message class ConcreteMediator(Mediator): def Send(self,message,col): if(col==col1): col2.Notify(message) else: col1.Notify(message) if __name__ == "__main__": m =ConcreteMediator() col1 = Colleague1(m) col2 = Colleague1(m) m.col1=col1 m.col2=col2 col1.Send("How are you?"); col2.Send("Fine.");

import sysclass WebSite:def Use(self): pass class ConcreteWebSite(WebSite): def __init__(self,strName): self.name = strName def Use(self,user): print "Website type:%s,user:%s" %(self.name,user) class UnShareWebSite(WebSite): def __init__(self,strName): self.name = strName def Use(self,user): print "UnShare Website type:%s,user:%s" %(self.name, user) class WebFactory: def __init__(self): test = ConcreteWebSite("test") self.webtype ={"test":test} self.count = {"test":0} def GetWeb(self,webtype): if webtype not in self.webtype: temp = ConcreteWebSite(webtype) self.webtype[webtype] = temp self.count[webtype] =1 else: temp = self.webtype[webtype] self.count[webtype] = self.count[webtype]+1 return temp def GetCount(self): for key in self.webtype: #print "type: %s, count:%d" %(key,sys.getrefcount(self.webtype[key])) print "type: %s, count:%d " %(key,self.count[key]) if __name__ == "__main__": f = WebFactory() ws=f.GetWeb("blog") ws.Use("Lee") ws2=f.GetWeb("show") ws2.Use("Jack") ws3=f.GetWeb("blog") ws3.Use("Chen") ws4=UnShareWebSite("TEST") ws4.Use("Mr.Q") print f.webtype f.GetCount() 

class Context:def __init__(self):self.input="" self.output="" class AbstractExpression: def Interpret(self,context): pass class Expression(AbstractExpression): def Interpret(self,context): print "terminal interpret" class NonterminalExpression(AbstractExpression): def Interpret(self,context): print "Nonterminal interpret" if __name__ == "__main__": context= "" c = [] c = c + [Expression()] c = c + [NonterminalExpression()] c = c + [Expression()] c = c + [Expression()] for a in c: a.Interpret(context)

# -*- coding: UTF-8 -*-
class Person:def Accept(self,visitor): pass class Man(Person): def Accept(self,visitor): visitor.GetManConclusion(self) class Woman(Person): def Accept(self,visitor): visitor.GetWomanConclusion(self) class Action: def GetManConclusion(self,concreteElementA): pass def GetWomanConclusion(self,concreteElementB): pass class Success(Action): def GetManConclusion(self,concreteElementA): print "男人成功时，背后有个伟大的女人" def GetWomanConclusion(self,concreteElementB): print "女人成功时，背后有个不成功的男人" class Failure(Action): def GetManConclusion(self,concreteElementA): print "男人失败时，闷头喝酒，谁也不用劝" def GetWomanConclusion(self,concreteElementB): print "女人失败时，眼泪汪汪，谁也劝不了" class ObjectStructure: def __init__(self): self.plist=[] def Add(self,p): self.plist=self.plist+[p] def Display(self,act): for p in self.plist: p.Accept(act) if __name__ == "__main__": os = ObjectStructure() os.Add(Man()) os.Add(Woman()) sc = Success() os.Display(sc) fl = Failure() os.Display(fl)