Home Accessibility Courses Diary The Mouth Forum Resources Site Map About Us Contact
inherited and associated / composite objects
Applying OO design techniques and best practise example from a Well House Consultants training course
More on Applying OO design techniques and best practise [link]

This example is described in the following article(s):
   • Inheritance, Composition and Associated objects - when to use which - Python example - [link]

Source code: t6 Module: Y116

# We have TABLES of various sorts in a room
# Associated with each table we have a waitress and multiple customers

# We're running a restuarant, seating guests, etc!

class person (object):
        def getname(this):
                return this.name

class customer(person):
        def __init__(this,name,partysize):
                this.name = name
                this.partysize = partysize
        def getsize(this):
                return this.partysize

class waitress(person):
        def __init__(this,name,capacity):
                this.name = name
                this.capacity = capacity
                this.ccc = 0 # current customer count / not yet used

# ---------------------------------------------------

class table(object):
        def __init__(current,material,w,h,wt):
                current.sng(material,wt)
                current.w = w
                current.h = h
                current.place = 925
        def getbums(current):
                side = int(current.w/current.place)
                wide = int(current.h/current.place)
                return 2 * (side + wide)
        def setplace(current,p):
                current.place = p
        def getdoggie(current):
                if current.w < current.h:
                        return current.w/2
                return current.h/2
        def sng(current,material,wt):
                current.wt = wt
                current.m = material
                current.parties = []
        def getwaitstaff(self):
                return self.wt.getname()
        def seatguests(self,pname):
                so_far = self.getseated() # already at table
                adding = pname.getsize() # wanting to join
                holds = self.getbums() # capacity of table

                if holds >= so_far + adding:
                        self.parties.append(pname)
                        return True

                return None

        def getseated(self):
                so_far = 0
                for pty in self.parties:
                        so_far += pty.getsize()
                return so_far

class recttable(table):
        pass

class squaretable(table):
        def __init__(current,material,w,wt):
                current.sng(material,wt)
                current.w = w
                current.h = w
                current.place = 925

class roundtable(table):
        def __init__(current,material,w,wt):
                current.sng(material,wt)
                current.w = w
                current.h = w
                current.place = 800
        def getbums(current):
                side = int(current.w * 3.14159265 / current.place)
                return side

# ----------------------------------------------

if __name__ == "__main__":

        lead = waitress("Heather",12)
        assist = waitress("Poppy",10)

        cafe = [recttable("Cherry",2100,980,lead),
                recttable("Plastic",1800,750,assist),
                roundtable("Ash",1500,lead),
                squaretable("oak",5000,assist) ]

        for tab in cafe:
                ps1 = tab.getbums()
                dog = tab.getdoggie()
                order = tab.getwaitstaff()
                print "We can seat",ps1,"and doggie distance is",dog,"order from",order

        if cafe[0].seatguests(customer("Alex",4)):
                print "We have seated Alex"

        if cafe[0].seatguests(customer("Simon",3)):
                print "We have seated Simon"

        for tab in cafe:
                ps1 = tab.getbums()
                ps2 = tab.getseated()
                order = tab.getwaitstaff()
                print "We have",ps2,"at a table for",ps1,"looked after by",order

# ------------------------------------------------------

""" Sample Output

munchkin:opy grahamellis$ python tabby
We can seat 6 and doggie distance is 490 order from Heather
We can seat 2 and doggie distance is 375 order from Poppy
We can seat 5 and doggie distance is 750 order from Heather
We can seat 20 and doggie distance is 2500 order from Poppy
We have seated Alex
We have 4 at a table for 6 looked after by Heather
We have 0 at a table for 2 looked after by Poppy
We have 0 at a table for 5 looked after by Heather
We have 0 at a table for 20 looked after by Poppy
munchkin:opy grahamellis$

"""

Learn about this subject
This module and example are covered on the following public courses:
 * Learning to program in Python
 * Python Programming
 * Intermediate Python
Also available on on site courses for larger groups

Books covering this topic
Yes. We have over 700 books in our library. Books covering Python are listed here and when you've selected a relevant book we'll link you on to Amazon to order.

Other Examples
This example comes from our "Applying OO design techniques and best practise" training module. You'll find a description of the topic and some other closely related examples on the "Applying OO design techniques and best practise" module index page.

Full description of the source code
The complete module that describes this example is available for download under our Open Training Notes License from our sister site http://www.training-notes.co.uk.

Other resources
• Our Solutions centre provides a number of longer technical articles.
• Our Opentalk forum archive provides a question and answer centre.
The Horse's mouth provides a daily tip or thought.
• Further resources are available via the resources centre.
• All of these resources can be searched through through our search engine
• And there's a global index here.

Purpose of this website
This is a sample program, class demonstration or answer from a training course. It's main purpose is to provide an after-course service to customers who have attended our public private or on site courses, but the examples are made generally available under conditions described below.

Web site author
This web site is written and maintained by Well House Consultants.

Conditions of use
Past attendees on our training courses are welcome to use individual examples in the course of their programming, but must check the examples they use to ensure that they are suitable for their job. Remember that some of our examples show you how not to do things - check in your notes. Well House Consultants take no responsibility for the suitability of these example programs to customer's needs.

This program is copyright Well House Consultants Ltd, but is part of a module released under our Open Training Notes license. You may use it for your own training needs provided that you adhere to the conditions laid down. In summary, these require you (a) to make no charge for the training and (b) to include a full copy of our copyright statement with the material your distribute.

Any of our images within this code may NOT be reused on a public URL without our prior permission. For Bona Fide personal use, we will often grant you permission provided that you provide a link back. Commercial use on a website will incur a license fee for each image used - details on request.

You can Add a comment or ranking to this page

© WELL HOUSE CONSULTANTS LTD., 2014: Well House Manor • 48 Spa Road • Melksham, Wiltshire • United Kingdom • SN12 7NY
PH: 01144 1225 708225 • FAX: 01144 1225 899360 • EMAIL: info@wellho.net • WEB: http://www.wellho.net • SKYPE: wellho

PAGE: http://www.wellho.net/resources/ex.php4 • PAGE BUILT: Sat Apr 13 08:12:34 2013 • BUILD SYSTEM: wizard