Spring Resful Client with RestTemplate

Question

I'm using RestTemplate class to get All user but when i run Main in Client then occur error, i don't know why ???

Exception in thread "main" java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to edu.java.spring.service.user.model.User at edu.java.spring.service.client.RestClientTest.main(RestClientTest.java:33)

Here file RestClientTest.java

public class RestClientTest {

    public static void main(String[] args) throws IOException{
        List<User> users = getUsers();
        for (int i = 0; i < users.size(); i++) {
            System.out.println("Rest Response" + loadUser(users.get(i).getUserName()));
        }

    }
    public static List<User> getUsers(){
        String uri = new String("http://localhost:8080/rest/user/list");
        RestTemplate rt = new RestTemplate();
        return (List<User>) rt.getForObject(uri,List.class);
    }

    public static String loadUser(String username) throws IOException {
        String url = "http://localhost:8080/rest/user/json/" + username;

        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();
        con.setRequestMethod("GET");
        con.setRequestProperty("Accept", "application/json");
        InputStream stream = con.getInputStream();
        BufferedReader in = new BufferedReader(new InputStreamReader(stream));
        String inputLine;
        StringBuffer response = new StringBuffer();
        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        return response.toString();

    }

Here file UserRestServiceController.java

   @Controller
public class UserRestServiceController {
    @Autowired
    public  UserDao userDao;
    @Autowired
    public View jsonTemplate;
    @RequestMapping(value = "/rest/user/list", produces = MediaType.APPLICATION_JSON_VALUE,method = RequestMethod.GET)
    public @ResponseBody List<User> getUsers(){
        return userDao.listUsers();
    }
    @RequestMapping(value="/rest/user/json/{username}")
    public ModelAndView loadUser(@PathVariable("username")String name){
        return new ModelAndView(jsonTemplate,"data",userDao.loadUser(name));
    }

@dunni, statement in for function. `System.out.println("Rest Response" + loadUser(users.get(i).getUserName()));` — Dat Pham, Mar 30 '16 at 09:52
Then can you please post the controller, which is mapped to "http://localhost:8080/rest/user/json/" + username? — dunni, Mar 30 '16 at 11:37
Why do you return a ModelAndView instance from the loadUser method? Just return the User object and add the ResponseBody annotation, like at the getUsers method. This should work. — dunni, Mar 30 '16 at 23:05
@dunni, thank your answer, but this is'nt way to solve problem. — Dat Pham, Mar 30 '16 at 23:23
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/107795/discussion-between-dat-pham-and-dunni). — Dat Pham, Mar 30 '16 at 23:27

score -1 · Answer 1 · edited May 23 '17 at 12:07

-1

I believe the following method is not returning as you expect:

rt.getForObject(uri,List.class);

Take a look at this question as it might help you also fix your error. ClassCastException: RestTemplate returning List instead of List

edited May 23 '17 at 12:07

Community

1
1

answered Mar 30 '16 at 17:37

ashleygrant

29
1

relace `rt.getForObject(uri,List.class)` by `rt.getForObject(uri,User[].class)` – Dat Pham Mar 30 '16 at 23:25

Spring Resful Client with RestTemplate

1 Answers1