@PathVariable, @RequestBody, @ApiParam, similar annotations, may be removed if they're present on superclass or interface

[sambsnyd]

There are various spring annotations, including but not limited to @PathVariable, @RequestBody, @Valid, @Size, @ApiParam, @Pattern, which allow developers to tell spring about the contract their API has.

If these annotations are present on a superclass or interface being implemented then they can be removed from the subclass.
Leaving them isn't necessarily harmful so long as the arguments of the duplicated annotations match. If the arguments do not match it's a spring runtime error. So this is a "best practices & hygiene" rather than an "essential for migration" sort visitor.

[sambsnyd]

Turns out this is really hard/ almost impossible with our current API. We just don't have enough information on JavaType.Class about what methods and what annotations are on those methods to be able to do this correctly.

[sambsnyd]

• This issue is blocked until JavaType.Class should contain full info on annotations, methods, constructors, superclasses rewrite#150 is implemented

[arodionov]

It seems, there is still no way to get all the required annotations for a superclass/interface.

For example, having an interface:

public interface UserApi {
    @PostMapping("/users/{id}")
    String updateUser(
        @PathVariable("id") Long id,
        @RequestBody UserData request
    );
}

and the UserController implementation:

@RestController
public class UserController implements UserApi {

    @Override @PostMapping("/users/{id}")
    public String updateUser(
        @PathVariable("id") Long id,
        @RequestBody UserData request
    ) {
        return "User " + id + " updated: " + request.getFirstName() + " " + request.getLastName();
    }
}

The JavaType.Method for UserApi#updateUser has method annotations but doesn't have method parameters annotations:

[timtebeek]

• blocked by 🚧 Add annotations to the type attribution for method parameters rewrite#5337