FilesExpand file tree

 master

/

bridge.py

Copy path

BlameMore file actions

BlameMore file actions

Latest commit

 

History

History

History

55 lines (39 loc) · 1.25 KB

 master

/

bridge.py

Top

File metadata and controls

• Code
• Blame

55 lines (39 loc) · 1.25 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

#!/usr/bin/env python

# -*- coding: utf-8 -*-

"""

*References:

http://en.wikibooks.org/wiki/Computer_Science_Design_Patterns/Bridge_Pattern#Python

*TL;DR80

Decouples an abstraction from its implementation.

"""

# ConcreteImplementor 1/2

class DrawingAPI1(object):

def draw_circle(self, x, y, radius):

print('API1.circle at {}:{} radius {}'.format(x, y, radius))

# ConcreteImplementor 2/2

class DrawingAPI2(object):

def draw_circle(self, x, y, radius):

print('API2.circle at {}:{} radius {}'.format(x, y, radius))

# Refined Abstraction

class CircleShape(object):

def __init__(self, x, y, radius, drawing_api):

self._x = x

self._y = y

self._radius = radius

self._drawing_api = drawing_api

# low-level i.e. Implementation specific

def draw(self):

self._drawing_api.draw_circle(self._x, self._y, self._radius)

# high-level i.e. Abstraction specific

def scale(self, pct):

self._radius *= pct

def main():

shapes = (CircleShape(1, 2, 3, DrawingAPI1()), CircleShape(5, 7, 11, DrawingAPI2()))

for shape in shapes:

shape.scale(2.5)

shape.draw()

if __name__ == '__main__':

main()

### OUTPUT ###

# API1.circle at 1:2 radius 7.5

# API2.circle at 5:7 radius 27.5