RetrofitForDummies.java

public class HelloWorld {

	private static final int TIMEOUT = 120;
	private static final String BASE = "https://randomuser.me/";

	public static void main(String[] args) {

		System.out.println("Hello");

		HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
		logging.setLevel(HttpLoggingInterceptor.Level.BODY);

		OkHttpClient client = new OkHttpClient.Builder()
			.connectTimeout(TIMEOUT, TimeUnit.SECONDS)
			.writeTimeout(TIMEOUT, TimeUnit.SECONDS)
			.readTimeout(TIMEOUT, TimeUnit.SECONDS)
			.addInterceptor(logging)
			.build();

		Retrofit retrofit = new Retrofit.Builder()
			.baseUrl(BASE)
			.addConverterFactory(GsonConverterFactory.create())
			.client(client)
			.build();


		System.out.println("Init call");

		retrofit.create(Service.class).getUser().enqueue(new Callback<JsonObject>() {

			@Override
			public void onResponse(Call<JsonObject> arg0, Response<JsonObject> arg1) {
				System.out.println("Response");
				System.out.println(arg1.body());
			}

			@Override
			public void onFailure(Call<JsonObject> arg0, Throwable arg1) {
				System.out.println("When call failure");
				System.err.println(arg1.toString());
			}
		});
	}

	public interface Service {

		@GET("/api")
		Call<JsonObject> getUser();
	}

}