call rest api using java code

package cloud.interworks.bss.api.client;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Base64;
import org.json.JSONObject;

public class Main {
 
    private static final String BASE_URL = "http://beta.gocloud360.net";
    private static final String CLIENT_ID = "c5378d41-c97d-490e-868e-83667e2f530e";
    private static final String CLIENT_SECRET = "vvDzsClZZ/V3f4TM1SmkFgCfbesY8bPMYGO4TwSWfKw=";
    private static final String USERNAME = "dev_test";
    private static final String PASSWORD = "dev_test";

    public static void main(String[] args) {
        try {
            // Get access token.
            System.out.println("Starting request for access token..");
            String token = getAccessToken();
            System.out.println("Successfully received access token..\n\n" + token);
         
            // Make the API call.
            System.out.println("\n------------------------------\nStarting API call..");
            int accountID = 1;
            String response = getAccountData(token, accountID);
            System.out.println("Successfully called API method..\n\n" + response);
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
 
    private static String getAccessToken() throws Exception {
        URL url = new URL(BASE_URL + "/oauth/token");
        HttpURLConnection conn = (HttpURLConnection)url.openConnection();
        conn.setRequestMethod("POST");
        String base64Input = CLIENT_ID + ":" + CLIENT_SECRET;
        String encoded = Base64.getEncoder().encodeToString(base64Input.getBytes());
        conn.setRequestProperty("Authorization", "Basic " + encoded);
     
        String params = "grant_type=password&username=" + USERNAME + "&password=" + PASSWORD;
        conn.setDoOutput(true);
        try (DataOutputStream os = new DataOutputStream(conn.getOutputStream())) {
            os.writeBytes(params);
            os.flush();
        }
     
        StringBuilder sb = new StringBuilder();
        try (BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()))) {
            String line;
            while((line = br.readLine()) != null) {
                sb.append(line);
            }
        }
     
        JSONObject json = new JSONObject(sb.toString());
        return json.getString("access_token");
    }
 
    private static String getAccountData(String token, int accountID) throws Exception {
        URL url = new URL(BASE_URL + "/api/accounts/" + accountID + "/syncoptions");
        HttpURLConnection conn = (HttpURLConnection)url.openConnection();
        conn.setRequestMethod("GET");
        conn.setRequestProperty("Authorization", "Bearer " + token);
conn.setRequestProperty("X-Api-Version", "latest");
     
        StringBuilder sb = new StringBuilder();
        try (BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()))) {
            String line;
            while((line = br.readLine()) != null) {
                sb.append(line);
            }
        }
     
        return sb.toString();
    }
}