Python Design Patterns 简明教程
Python Design Patterns - Abstract Factory
抽象工厂模式也被称为工厂的工厂。这个设计模式属于创建型设计模式类别。它提供了创建对象的最佳方式之一。
它包括一个负责创建与工厂相关的对象的接口。
How to implement the abstract factory pattern?
下面的程序有助于实现抽象工厂模式。
class Window:
__toolkit = ""
__purpose = ""
def __init__(self, toolkit, purpose):
self.__toolkit = toolkit
self.__purpose = purpose
def getToolkit(self):
return self.__toolkit
def getType(self):
return self.__purpose
class GtkToolboxWindow(Window):
def __init__(self):
Window.__init__(self, "Gtk", "ToolboxWindow")
class GtkLayersWindow(Window):
def __init__(self):
Window.__init__(self, "Gtk", "LayersWindow")
class GtkMainWindow(Window):
def __init__(self):
Window.__init__(self, "Gtk", "MainWindow")
class QtToolboxWindow(Window):
def __init__(self):
Window.__init__(self, "Qt", "ToolboxWindow")
class QtLayersWindow(Window):
def __init__(self):
Window.__init__(self, "Qt", "LayersWindow")
class QtMainWindow(Window):
def __init__(self):
Window.__init__(self, "Qt", "MainWindow")
# Abstract factory class
class UIFactory:
def getToolboxWindow(self): pass
def getLayersWindow(self): pass
def getMainWindow(self): pass
class GtkUIFactory(UIFactory):
def getToolboxWindow(self):
return GtkToolboxWindow()
def getLayersWindow(self):
return GtkLayersWindow()
def getMainWindow(self):
return GtkMainWindow()
class QtUIFactory(UIFactory):
def getToolboxWindow(self):
return QtToolboxWindow()
def getLayersWindow(self):
return QtLayersWindow()
def getMainWindow(self):
return QtMainWindow()
if __name__ == "__main__":
gnome = True
kde = not gnome
if gnome:
ui = GtkUIFactory()
elif kde:
ui = QtUIFactory()
toolbox = ui.getToolboxWindow()
layers = ui.getLayersWindow()
main = ui.getMainWindow()
print "%s:%s" % (toolbox.getToolkit(), toolbox.getType())
print "%s:%s" % (layers.getToolkit(), layers.getType())
print "%s:%s" % (main.getToolkit(), main.getType())