403 error - JAVA 1.8

[XinwangN]

Our system does not support java.net.http.HttpClient, so I have to use java.net.URLConnection

I got 403 error

403 Forbidden
Exception in thread "main" java.io.IOException: Server returned HTTP response code: 403 for URL: https://authz.constantcontact.com/oauth2/default/v1/token?code={authcode}&redirect_uri={url}&grant_t...

Here is my Java code,

        URL url = new URL("https://authz.constantcontact.com/oauth2/default/v1/token?code="+authCode+"&redirect_uri="+redirectUri+"&grant_type=authorization_code");

        HttpURLConnection http = (HttpURLConnection)url.openConnection();

        http.setRequestMethod("POST");

        http.setDoOutput(true);

        http.setRequestProperty("Accept", "application/json");

        http.setRequestProperty("Authorization", authHeader);

        http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

        http.setRequestProperty("Content-Length", "0");

        System.out.println(http.getResponseCode() + " " + http.getResponseMessage());

        StringBuffer temp = new StringBuffer();

        Scanner scan = new Scanner(http.getInputStream(), "UTF-8");

        // Scanner scan = new Scanner(http.getInputStream());

        while (scan.hasNext()) {

           temp.append(scan.nextLine());

        }

        scan.close();

        http.disconnect();

[Courtney_E]

Hello XinwangN,

Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.

Based on our logs for your account, it looks like you may have already resolved your issue.

However, if you still need assistance, please feel free to contact us directly/securely via email at webservices@constantcontact.com and reference case #30215783.  

Within your email, please also include the API key that you are using to make the request, the full request(s) where you are receiving the response error (including URL, headers, timestamp, and request body), and the full response body so that we can so that we can better assist you in identifying the root cause of the issue.

Please let us know if you have any other questions!