Java http get request slower than postman get request

I'm trying to send a get request in order to get a website content. When I'm using Postman it takes about 70-100 ms, but when I use the following code:

String getUrl = "someUrl";

URL obj = new URL(getUrl);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();

// optional default is GET
con.setRequestMethod("GET");

//add request header
con.setRequestProperty("User-Agent", "Mozilla/5.0");
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();

while ((inputLine = in.readLine()) != null)
{
    response.append(inputLine);
}
in.close();

response.toString();

it takes about 3-4 seconds.

Any idea how to get my code work as fast as Postman?

Thanks.