Could not read JSON: Can not deserialize instance of hello.Country[] out of START_OBJECT token

Question

I have rest url that gives me all countries - http://api.geonames.org/countryInfoJSON?username=volodiaL.

I use RestTemplate from spring 3 to parse returned json into

Answer 1

Another solution:

public class CountryInfoResponse {
  private List<Object> geonames;
}

Usage of a generic Object-List solved my problem, as there were other Datatypes like Boolean too.

Answer 2

For Spring-boot 1.3.3 the method exchange() for List is working as in the related answer

Spring Data Rest - _links

Answer 3

You need to do the following:

public class CountryInfoResponse {

   @JsonProperty("geonames")
   private List<Country> countries; 

   //getter - setter
}

RestTemplate restTemplate = new RestTemplate();
List<Country> countries = restTemplate.getForObject("http://api.geonames.org/countryInfoJSON?username=volodiaL",CountryInfoResponse.class).getCountries();

It would be great if you could use some kind of annotation to allow you to skip levels, but it's not yet possible (see this and this)

Answer 4

If you want to avoid using an extra Class and List<Object> genomes you could simply use a Map.

The data structure translates into Map<String, List<Country>>

String resourceEndpoint = "http://api.geonames.org/countryInfoJSON?username=volodiaL";

Map<String, List<Country>> geonames = restTemplate.getForObject(resourceEndpoint, Map.class);

List<Country> countries = geonames.get("geonames");

Answer 5

In my case, I was getting value of <input type="text"> with JQuery and I did it like this:

var newUserInfo = { "lastName": inputLastName[0].value, "userName": inputUsername[0].value,
 "firstName": inputFirstName[0] , "email": inputEmail[0].value}

And I was constantly getting this exception

com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.String out of START_OBJECT token at [Source: java.io.PushbackInputStream@39cb6c98; line: 1, column: 54] (through reference chain: com.springboot.domain.User["firstName"]).

And I banged my head for like an hour until I realised that I forgot to write .value after this"firstName": inputFirstName[0].

So, the correct solution was:

var newUserInfo = { "lastName": inputLastName[0].value, "userName": inputUsername[0].value,
 "firstName": inputFirstName[0].value , "email": inputEmail[0].value}

I came here because I had this problem and I hope I save someone else hours of misery.

Cheers :)