python 代码实现示例：
class Shape(object):
def draw(self):
pass
class RectangleImplementsShape(Shape):
def __init__(self):
print("this relalize Interface")
def draw(self):
print("Inside Rectangle::draw() method.")
class SquareImplementsShape(Shape):
def __init__(self):
print("this relalize Interface")
def draw(self):
print("Inside Square::draw() method.")
class CircleImplementsShape(Shape):
def __init__(self):
print("this relalize Interface")
def draw(self):
print("Inside Circle::draw() method.")
class ShapeFactory(object):
def __init__(self):
print("ShapeFactory init")
def getShape(self,method):
if method.lower() == 'rectangle':
return RectangleImplementsShape()
if method.lower() == 'square':
return SquareImplementsShape()
if method.lower() == 'circle':
return CircleImplementsShape()
shapeFactory = ShapeFactory()
shap1 = shapeFactory.getShape('Rectangle')
shap2 = shapeFactory.getShape('Square')
shap3 = shapeFactory.getShape('Circle')
shap1.draw()
shap2.draw()
shap3.draw() 
