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completion of example t6 - add factory, comparator, etc
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]
Source code: t7 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! # to example t6, we have added some further OO demos # - a factory method (static call that returns a constructor) # - a comparator to compare two objects derived from the same base # - a static method to compare a whole list of similar objects # - a method to print out an object by overriding the default 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 def findplace(tablist,client): for t in tablist: if t.seatguests(client): placed = 1 break else: placed = None return placed findplace = staticmethod(findplace) # Now an oldfashioned way, still works @staticmethod # This is the new way - a.k.a. "decorator" def myFactory(sourcestring): els = sourcestring.split(" ") print els if els[0] == "Re": server = waitress(els[3],10) # Should really have called method to search for this waitress # and then re-used her! return recttable(els[4],int(els[1]),int(els[2]),server) elif els[0] == "Ro": # code to be written pass elif els[0] == "Sq": # code to be written pass else: print "oops" return None def __str__(self): whattype = self.__class__.__name__ # Above would be better as call to "gettype" on object to return English text rz = "A " + whattype + " made of " + self.m + "." return rz def getmore(this,that): s1 = this.getbums() s2 = that.getbums() if s1 > s2: return this return that @staticmethod def getmost(these): sofar = these[0] for maybe in these[1:]: sofar = sofar.getmore(maybe) return sofar 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) ] # line of data that needs converting to object: fromfile = "Re 1500 2100 Rachel Teak 2005" cafe.append(table.myFactory(fromfile)) 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 not table.findplace(cafe,customer("Alex",4)): print "nowhere for Alex" if not table.findplace(cafe,customer("Simon",3)): print "nowhere for Simon" if not table.findplace(cafe,customer("Bob",2)): print "nowhere for Bob" if not table.findplace(cafe,customer("Santa",122)): print "nowhere for Santa" if not table.findplace(cafe,customer("Sally",3)): print "nowhere for Sal" for tab in cafe: ps1 = tab.getbums() ps2 = tab.getseated() order = tab.getwaitstaff() print tab,"We have",ps2,"at a table for",ps1,"looked after by",order # comparator moreseats = cafe[2].getmore(cafe[4]) print "More seats on",moreseats mostseats = table.getmost(cafe) print "Most seats on",mostseats # ------------------------------------------------------ munchkin:opy grahamellis$ python t7 ['Re', '1500', '2100', 'Rachel', 'Teak', '2005'] 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 can seat 6 and doggie distance is 750 order from Rachel nowhere for Santa A recttable made of Cherry. We have 6 at a table for 6 looked after by Heather A recttable made of Plastic. We have 0 at a table for 2 looked after by Poppy A roundtable made of Ash. We have 3 at a table for 5 looked after by Heather A squaretable made of oak. We have 3 at a table for 20 looked after by Poppy A recttable made of Teak. We have 0 at a table for 6 looked after by Rachel More seats on A recttable made of Teak. Most seats on A squaretable made of oak. munchkin:opy grahamellis$ Learn about this subject
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