Handle multiple JSON repsponse while calling foreign api using RestTemplate

Question

i am using rest template for calling foreign api and add into my dto class.

controller

    public ResponseEntity<CountResponse> count(@Validated @RequestBody CountRequest homeRequest){
        String uri = “http://localhost:8089/abc?email=" + homeRequest.getEmail();
        CountResponse result = restTemplate.getForObject(uri, CountResponse.class);
        return ResponseEntity.ok(result);
    }

DTO

@Data
public class CountResponse {
    @JsonProperty(value = "PendingCount")
    private int pendingCount;
    @JsonProperty(value = "todayPendingCount")
    private int todayPendingCount;
}

i am getting below response when success.

    "PendingCount": 1,
    "todayPendingCount": 0
} 

and getting

{
    "error": "No Record found"
}

when not data found ,

How to map error response to my dto class when JSON response is different??

Answer 1

Usually the error will be returned with an http-400 which can me checked before deserialising the error using a specific error class.

If that is not the case your CountResponse should have an error field, either directly or via inheritance.

I suggest inheritance because the api may return different objects for different calls but always the same error structure and it leaves the class definitions looking a little cleaner.