INTUIT JAVA API: AUTHORIZATION (JAVA TO QUICKBOOKS ONLINE INTEGRATION)

Basic code for REQUEST TOKEN, REQUEST TOKEN SECRET & Authorization URL:

void GetRequestToken() {
        // Invoke the helper class and retrieve the request token.
        OAuthConsumer oauthconsumer;       
        // Initialize the Provider class with the request token, access token and authorize URLs
        OAuthProvider provider = new DefaultOAuthProvider(<REQUEST_TOKEN_URL>, <ACCESS_TOKEN_URL>, <AUTHORIZE_URL>);
        try {
                oauthconsumer = new DefaultOAuthConsumer("<OAUTH_CONSUMER_KEY>", "<OAUTH_CONSUMER_SECRET>");
                // The retrieveRequestToken method in the signpost library calls the request token URL configured in the OAuthProvider object
                // to retrieve the token and sends the response to the URL configured in the Oauth Callback URL configured in the properties file
                String authUrl = provider.retrieveRequestToken(oauthconsumer, "https://oauth.intuit.com/oauth/v1/get_request_token");
                       
                System.out.println("AuthURL - " + authUrl);
                System.out.println("RequestToken - " + oauthconsumer.getToken());
                System.out.println("RequestTokenSecret - " + oauthconsumer.getTokenSecret());           
         System.out.println(provider.getAccessTokenEndpointUrl());                
            } catch (Exception e) {
            e.printStackTrace();
        }
    } 

Basic code for ACCESS TOKEN and ACCESS TOKEN SECRET: 

void GetAccessToken() {

        OauthHelper oauthhelper = new OauthHelper();     
        final Map<String, String> accesstokenmap = oauthhelper.getAccessToken(
                "<OAUTH_VERIFIER>",
                                "<REQUEST_TOKEN>",
                                "<REQUEST_TOKEN_SECRET>");
    }
 

Basic code for DataService object: 

DataService GetService(String <OAUTH_CONSUMER_KEY>, String <OAUTH_CONSUMER_SECRET>, String <ACCESS_TOKEN>, String <ACCESS_TOKEN_SECRET>, String realmId) throws FMSException {       

        IAuthorizer authorizer = new OAuthAuthorizer(<OAUTH_CONSUMER_KEY>, <OAUTH_CONSUMER_SECRET>, <ACCESS_TOKEN>, <ACCESS_TOKEN_SECRET>);
        Context context = new Context(authorizer, ServiceType.QBO, realmId);
        DataService service = new DataService(context);

        return service;
    }