How to urlencode using HttpClient

ElasticEmailClient.java

    public static String sendViaHttpClient(String userName, String apiKey, String from, String fromName, String subject, String body, String to) {

        NameValuePair[] data = {
            new BasicNameValuePair("userName", userName),
                new BasicNameValuePair("api_key", apiKey),
                new BasicNameValuePair("from", from),
                new BasicNameValuePair("from_name", fromName),
                new BasicNameValuePair("subject", subject),
                new BasicNameValuePair("body_html", body),
                new BasicNameValuePair("to", to)
        };

        try {
            org.apache.http.client.HttpClient client = new DefaultHttpClient();
            HttpPost post = new HttpPost("https://api.elasticemail.com/mailer/send");
            post.setEntity(new UrlEncodedFormEntity(data));
            HttpResponse response = client.execute(post);
            System.out.println(response);

        } catch (URISyntaxException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        } catch (HttpException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        } catch (InterruptedException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        } catch (IOException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }
        return null;
    }