[FIXED] Spring RequestBody with either List<Object> or Object. Name for both are same "data"

Issue

I want to handle json request for List of Object and Object it self in the same Spring controller. Below is the exact example.

Json Request for Single Object:

{"data":{"prop":"123456","prop2":"123456"}}

Json Request for List of Objects:

{"data":[{"prop":"123456","prop2":"123456"},{"prop":"123456","prop2":"123456"}]}

My Controller is as follow.

@PostMapping(path="/path")
public @ResponseBody String getSomething(@RequestBody Input data){
     return service.getSomething(data);
}

I want to handle both of this requests in a single spring controller.

Appreciate your help. Thanks.

Solution

EDIT

You can create DTOs for your inputs but receive the @RequestBody as a JSON string and then parse it as a list or a single object request.

DTO for a request list:

public class InputDataList {

private List<Input> data;

// getters and setters
}

DTO for a single request object:

public class InputDataSingle {

private Input data;

// getters and setters
}

Then on your controller:

        @PostMapping(path="/path")
        public @ResponseBody String getSomething(@RequestBody String json){

    // this is better done in a service but for simplicity, I write it in the controller
    try {
    InputDataSingle data = new ObjectMapper().readValue(json, InputDataSingle.class);
    // If fails to parse as a single object, parse as a list
    } catch (Exception) (
    InputDataList data = new ObjectMapper().readValue(json, InputDataList.class);
             }
// handle objects in the service layer
        }

Answered By - Urosh T.
Answer Checked By - Candace Johnson (JavaFixing Volunteer)