how to choose one view out of many in controller ( i don't want if/else because i might have many views)

Question

if ( accountType = "admin" )
        return admin view
if ( accountType = "customer" )
        return customer view
if ( accountType = "user" )
        return user view
if ( accountType = "merketing" )
        return marketing view

and so on .......

Use a Switch statement: https://docs.oracle.com/javase/tutorial/java/nutsandbolts/switch.html — Baked Inhalf, Nov 14 '14 at 10:01
@BakedInhalf switch does not operate on string types until java 7 — WeMakeSoftware, Nov 14 '14 at 10:02
@Funtik Sure you can! http://stackoverflow.com/questions/338206/why-cant-i-switch-on-a-string — Baked Inhalf, Nov 14 '14 at 10:04
@Funtik Yes switch operates on String after java 7 [see](https://docs.oracle.com/javase/7/docs/technotes/guides/language/strings-switch.html) — Foolish, Nov 14 '14 at 10:04
@ArslanKhan: Instead of having one controller and switching there, you might want to have multiple, more simple controllers for each account type. — Markus W Mahlberg, Nov 14 '14 at 10:27

score 1 · Accepted Answer · answered Nov 14 '14 at 10:05

1

Use a map where you register your views with the given key:

viewsMap.put("admin", admin_view);
viewsMap.put("customer", customer_view);
...

and then, just do:

View view = viewsMap.get(accountType);
if (view == null) {
    return error_view;
}
return view;

answered Nov 14 '14 at 10:05

cello

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still there will be processing in maps i want one line solution and want open closed principal – Arslan Khan Nov 14 '14 at 10:08
1

I don't think it can be done in one line, kind of matching the value of accountType to a variable name or something like this. Using a map is the closest you can get: one line to retrieve it (if you do not do any error checking), and one line for each view to register. – cello Nov 14 '14 at 10:10
i am kinda thinking putting it in DB then retrieve it concat it with base url. like redirectTo (baseURL + role + ".jsp"); – Arslan Khan Nov 14 '14 at 10:34
probably you should make your pseudo-code in the question a bit clearer. What do you want to return? a (complex?) view object, or just a String, for example a URL? It's really not clear from your question, especially as you don't say if and what framework you use. If it's just a string, I think Foolish had a nice solution he might post again. – cello Nov 14 '14 at 10:40

score 1 · Answer 2 · answered Nov 14 '14 at 10:06

1

You can put it into HashMap and then just get it from there ;)

answered Nov 14 '14 at 10:06

Maksym

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still there will be processing in maps i want one line solution and want open closed principal – Arslan Khan Nov 14 '14 at 10:08

score 0 · Answer 3 · answered Nov 14 '14 at 10:13

If you want to separate the creation code, use a simplified factory:

class ViewFactory {
   public static View createView(String viewName)
   {
        if( viewName = admin )
            return new AdminView();

   }
}

You can do this is your views implement a common interface.

how to choose one view out of many in controller ( i don't want if/else because i might have many views)

3 Answers3