erlang与设计模式（二）——工厂、抽象工厂、建造者

 1 -module(chinese_cook).
 2 -author("Russell-X-Shanso").
 3 
 4 -behaviour( factory ).
 5 -behaviour( abstract_factory ).
 6 -behaviour( builder ).
 7 
 8 %% API
 9 -export([ do_best_food/0 ]).
10 -export([ do_duck/0, do_beef/0, do_vegetables/0 ]).
11 -export([ do_breakfast/0, do_lunch/0, do_diner/0 ]).
12 
13 %%%%%%%%%%%%%%%%%%%%%%%
14 %% factory callback
15 do_best_food()->
16     { ok, <<"Roast Duck">> }.
17 
18 %%%%%%%%%%%%%%%%%%%%%%%
19 %% abstract_factory callback
20 do_duck() ->
21     { ok, <<"Roast Duck">> }.
22 
23 do_beef() ->
24     { ok, <<"Tomato beef stew">> }.
25 
26 do_vegetables() ->
27     { ok, <<"Carve radish">> }.
28 
29 %%%%%%%%%%%%%%%%%%%%%%%
30 %% builer callback
31 do_breakfast() ->
32     { ok, <<"Carve radish">> }.
33 
34 do_lunch() ->
35     { ok, <<"Tomato beef stew">> }.
36 
37 do_diner() ->
38     { ok, <<"Roast Duck">> }.

 1 -module(western_cook).
 2 -author("Russell-X-Shanso").
 3 
 4 -behaviour( factory ).
 5 -behaviour( abstract_factory ).
 6 -behaviour( builder ).
 7 
 8 %% API
 9 -export([ do_best_food/0 ]).
10 -export([ do_duck/0, do_beef/0, do_vegetables/0 ]).
11 -export([ do_breakfast/0, do_lunch/0, do_diner/0 ]).
12 
13 %%%%%%%%%%%%%%%%%%%%%%%
14 %% factory callback
15 do_best_food()->
16     { ok, <<"Duck liver">> }.
17 
18 %%%%%%%%%%%%%%%%%%%%%%%
19 %% abstract_factory callback
20 do_duck() ->
21     { ok, <<"Duck liver">> }.
22 
23 do_beef() ->
24     { ok, <<"Beefsteak">> }.
25 
26 do_vegetables() ->
27     { ok, <<"Salad">> }.
28 
29 %%%%%%%%%%%%%%%%%%%%%%%
30 %% builer callback
31 do_breakfast() ->
32     { ok, <<"Salad">> }.
33 
34 do_lunch() ->
35     { ok, <<"Duck liver">> }.
36 
37 do_diner() ->
38     { ok, <<"Beefsteak">> }.

 1 -module(korea_cook).
 2 -author("Russell-X-Shanso").
 3 
 4 -behaviour( factory ).
 5 -behaviour( abstract_factory ).
 6 -behaviour( builder ).
 7 
 8 %% API
 9 -export([ do_best_food/0 ]).
10 -export([ do_duck/0, do_beef/0, do_vegetables/0 ]).
11 -export([ do_breakfast/0, do_lunch/0, do_diner/0 ]).
12 
13 %%%%%%%%%%%%%%%%%%%%%%%
14 %% factory callback
15 do_best_food()->
16     { ok, <<"Pickle">> }.
17 
18 %%%%%%%%%%%%%%%%%%%%%%%
19 %% abstract_factory callback
20 do_duck() ->
21     { error, <<"Sorry, This cook Can‘t cook duck">> }.
22 
23 do_beef() ->
24     { error, <<"Sorry, This cook can‘t cook beef">> }.
25 
26 do_vegetables() ->
27     { ok, <<"Pickle">> }.
28 
29 %%%%%%%%%%%%%%%%%%%%%%%
30 %% builer callback
31 do_breakfast() ->
32     { ok, <<"Pickle">> }.
33 
34 do_lunch() ->
35     { ok, <<"Pickle">> }.
36 
37 do_diner() ->
38     { ok, <<"Pickle">> }.

 1 -module(factory).
 2 -author("Russell-X-Shanso").
 3 
 4 %% API
 5 -export([ cook1/1, cook2/1 ]).
 6 
 7 -callback do_best_food() -> { ok, binary() }.
 8 
 9 cook1( Style )->
10     { ok, Food } = case Style of
11         chinese -> chinese_cook:do_best_food();
12         western -> western_cook:do_best_food();
13         korea -> korea_cook:do_best_food()
14     end,
15     io:format( "Food is:~p~n", [ Food ] ).
16 
17 
18 cook2( Style )->
19     Cook = case Style of
20                chinese -> chinese_cook;
21                western -> western_cook;
22                korea -> korea_cook
23            end,
24     { ok, Food } = apply( Cook, do_best_food, [] ),
25     io:format( "Food is:~p~n", [ Food ] ).

 1 -module(abstract_factory).
 2 -author("Russell-X-Shanso").
 3 
 4 %% API
 5 -export([ cook/2 ]).
 6 
 7 
 8 -callback do_duck() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
 9 -callback do_beef() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
10 -callback do_vegetables() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
11 
12 cook( Style, Material ) ->
13     Cook = case Style of
14                chinese -> chinese_cook;
15                western -> western_cook;
16                korea -> korea_cook
17            end,
18     Action = case Material of
19                  duck -> do_duck;
20                  beef -> do_beef;
21                  vegetables -> do_vagetables
22              end,
23     case apply( Cook, Action, [] ) of
24         { ok, Food } -> io:format( "Food is:~p~n", [ Food ] );
25         { error, ErrorInfo } -> io:format( "Oops:~p~n", [ ErrorInfo ] )
26     end.

 1 -module(builder).
 2 -author("Russell-X-Shanso").
 3 
 4 %% API
 5 -export([ cook/1 ]).
 6 
 7 -callback do_breakfast() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
 8 -callback do_lunch() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
 9 -callback do_diner() -> { ok, binary() } | { error, ErrorInfo :: binary() }.
10 
11 cook( Style ) ->
12     Cook = case Style of
13                chinese -> chinese_cook;
14                western -> western_cook;
15                korea -> korea_cook
16            end,
17     director( Cook ).
18 
19 
20 director( Cook ) ->
21     { ok, Breakfast } = apply( Cook, do_breakfast, [] ),
22     io:format( "Breakfast: ~p~n", [ Breakfast ] ),
23     { ok, Lunch } = apply( Cook, do_lunch, [] ),
24     io:format( "Lunch: ~p~n", [ Lunch ] ),
25     { ok, Dinner } = apply( Cook, do_diner, [] ),
26     io:format( "Dinner: ~p~n", [ Dinner ] ).