Generic Spring MVC Controller with Inheritance

Question

Can I do the following in Spring MVC

Suppose I have the Base GenericController as follows with one request mapping "/list"

@Controller
public class GenericController<T>{

    @RequestMapping(method = RequestMethod.GET, value = "/list")
    public @ResponseBody List<T> getMyPage(){
        // returns list of T
    }

}

Below are my two controllers

@Controller(value = "/page1")
public class Page1Controller extends GenericController<Page1>{

}

@Controller(value = "/page2")
public class Page2Controller extends GenericController<Page2>{

}

Now will i be able to access the url "/page1/list" and "/page2/list" where first goes to Page1Controller and second goes to Page2Controller.

AFAIK, annotations are not inherited, so this may not work as expected — Arun P Johny, Mar 13 '13 at 10:41

Robin · Answer 1 · 2014-06-02T09:03:21.710

14

That's not possible and was already rejected, see SPR-10089. I think this would be somewhat confusing and in addition, it is very unlikely that those method behave exactly the same besides the different mapping. But you can use delegation instead:

public class BaseController<T> {
    public List<T> getPageList(){
        // returns list of T
    }
}

@Controller(value = "/page1")
public class Page1Controller extends BaseController<Page1>{
    @RequestMapping(method = RequestMethod.GET, value = "/list")
    public @ResponseBody List<Page1> getMyPage() {
      return super.getPageList();
    }    
}

@Controller(value = "/page2")
public class Page2Controller extends BaseController<Page2>{
    @RequestMapping(method = RequestMethod.GET, value = "/list")
    public @ResponseBody List<Page2> getMyPage() {
      return super.getPageList();
    }
}

edited Jun 02 '14 at 09:03

answered Apr 17 '13 at 15:44

Robin

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1

I think SPR-10089 does not fit this example, which should conceptually work. SPR-10089 will not "stack" url mappings on @RequestMapping on the class level. see this http://stackoverflow.com/questions/5268643/spring-mvc-requestmapping-inheritance for a complete explanation. – Nitzan Volman Oct 01 '14 at 18:31
In this example, should be ok to have a class level annotation, and method level annotations in the base class. – Nitzan Volman Oct 01 '14 at 18:33
how would that work? for each of the resources you usually have a CrudRepository or a similar Service.. by delegating to the parent how would you get the correct repository? You will need to pass that as an argument somehow, which would be ugly – Michail Michailidis Oct 15 '17 at 09:27
@robin It seems that this answer is out of date. Take a look at manish's answer. – Dariusz Oct 28 '20 at 11:21

manish · Answer 2 · 2016-02-24T03:18:46.737

8

For those looking for something similar with Spring Framework 4.x, the class hierarchy provided by the OP is possible. A sample application is available on Github. It allows users to view a list of books or a list of magazines as JSON.

edited Feb 24 '16 at 03:18

answered Nov 16 '15 at 05:20

manish

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5
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Why do you say that the super type does not have the `@RequestMapping` annotation? The super type `BaseController` does have the annotation on the `list` method which is what the first code snippet in the question shows. May be you have a different requirement and got confused? – manish Feb 22 '16 at 15:44
manish, you're right, sorry for wrong comment - I'll delete it and upvote ;-) Edit: The solution works fine for me, so IMO this is the correct answer. – Michael Wyraz Feb 23 '16 at 19:23

Generic Spring MVC Controller with Inheritance

2 Answers2