REST

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.HttpClientBuilder;

GsonBuilder builder = new GsonBuilder();
Gson gson = builder.create();

MojaKlasa mojObjekat = new MojaKlasa(); // Plain Old Java Object (getters+setters+no arg constructor)
String mojObjekatKaoJSON = gson.toJson(mojObjekat );
HttpResponse response = sendJSONPOST("http://localhost:8080/WebApp/urlKaMomRestServisu, mojObjekatKaoJSON);
System.out.println("RESPONSE FROM THE SERVER:\n" + response.toString());




    public static HttpResponse sendJSONPOST(String urlString, String data) throws Exception {
        HttpClientBuilder clientBuilder = HttpClientBuilder.create();
        HttpClient client = clientBuilder.build();
        HttpPost post = new HttpPost(urlString);
        StringEntity  postingString =new StringEntity(data);//convert your pojo to   json
        post.setEntity(postingString);
        post.setHeader("Content-type", "application/json");
        HttpResponse  response = client.execute(post);
        return response;
    }