Print the HttpPost request before send it on java

Question

I'm sending a Json message to an API, i'm getting an error but I want to know what I'm sending to the API. By the way the authentification method is by token access.

The method is this one:

    public static void sendRequestPost2(JSONObject json) throws IOException, JSONException {

    CloseableHttpClient httpClient = HttpClientBuilder.create().build();

    try {

        HttpPost request = new HttpPost(Config.urlJSON);
        StringEntity params = new StringEntity(json.toString());
        request.addHeader("Authorization", "Token " + Config.renamToken);
        request.addHeader("content-type", "application/json");
        request.setEntity(params);

        int statusCode = httpClient.execute(request).getStatusLine().getStatusCode();

        Log.debug("[STATUS:" + statusCode + "]");

    } catch (Exception ex) {
        Log.debug(ex.toString());
    } finally {
        httpClient.close();
    }
}

I have tried several gets of the request object but I'm getting the results separately:

    request.setEntity(params);

    Log.debug(request.getMethod());

    Header[] heads = request.getAllHeaders();

    String headsString = "";
    for (int i = 0; i < heads.length; i++) {
        headsString += heads[i];
    }
    String entity = EntityUtils.toString(request.getEntity());
    Log.debug(entity);
    Log.debug(request.getRequestLine().toString());
    Log.debug(headsString);
    Log.debug(request.getURI().toURL().toString());

    CloseableHttpResponse response = httpClient.execute(request);

    Log.debug(response.getStatusLine().toString());
    String content = EntityUtils.toString(response.getEntity());
    Log.debug(content);

I can get a lot of information but I'm not getting the full string before send it to the API and I need to know if the string is correct.

Thank you.