• Table of contents
• Programming Guide
  • Step-By-Step
  • Generate the form action URL
    • Input Parameters
    • Output Parameters
    • Code Snippets
  • Payment Status Callback
    • Input Parameters
    • Output Parameters
    • Code Snippets

Programming Guide¶

This guide describes how to make use of the NMI APIs for payment related transaction and it consists of 2 main parts:

• Step-By-Step - describes how to integrate the NMI payment gateway
• API Reference - the detailed description of all the APIs mentioned in Step-By-Step

The demo application can be found here:

http://192.168.2.68/ukstore/nmi-sample/orders.jsp

Step-By-Step¶

Before begin, install the following libraries into your development environment (remove the old versions if exists):

• HttpCore 4.1.2
• HttpClient 4.1.2

See also Payment Flow

Steps:

1. To get the form URL, pass the required parameters to getFormActionUrl method.
2. Use the form URL (in which obtained in the previous step) to construct the payment form with the following input elements:
   • billing-cc-number
   • billing-cc-exp
   • cvv
   • billing-first-name
   • billing-last-name
   • billing-address1
   • billing-city
   • billing-state
   • billing-postal
   • billing-country
   • billing-phone
   • billing-email
     • Example:
       
   • Notes: the URL of this payment form should be HTTPS
3. Validate all of the fields in the form using JavaScript (do not use server-side validation). The payment form will be submitted directly to the payment gateway and the payment gateway will direct the user back to the receipt page, which specified the in the previous step.
4. The redirect URL will contains the token-id query parameter. But the method, queryAndPersistPaymentStatus will extract the parameter on your behalf.
5. Use the order ID that returned by the method, queryAndPersistPaymentStatus to get the payment status in the Interface table.
6. The content of the receipt page is depends on the payment status.
7. done.

Generate the form action URL¶

Generates the form action URL which is needed in the self-hosted payment form.

Method Signature:

public static String getFormActionUrl(String orderId, String orderDescription, BigDecimal orderAmount, String returnUrl)

Input Parameters¶

• orderId - the unique ID for the order
• orderDescription - a simple description of the order
• orderAmount - the settlement amount of the order in 2 decimal places, e.g. 12.34
• returnUrl - the receipt URL

Output Parameters¶

Returns a form action URL

Code Snippets¶

    String orderId = request.getParameter("order-id");
    String orderDescription = request.getParameter("order-description");
    BigDecimal orderAmount = new BigDecimal(request.getParameter("order-amount"));
    String returnUrl = request.getParameter("return-url");

    String formUrl = PaymentUtils.getFormActionUrl(orderId, 
            orderDescription, 
            orderAmount, 
            returnUrl);

Payment Status Callback¶

Queries the payment status using the token ID that returned by NMI. After obtained the payment status, update the particular record in the Interface table.

Important: This method is supposed to be placed and invoked in the very beginning of the receipt page, (a.k.a. the returnUrl that specified in Generate form action URL).

Method Signature:

public static String queryAndPersistPaymentStatus(Connection dbConnection, HttpServletRequest servletRequest)

Input Parameters¶

• dbConnection - an established database connection
• servletRequest - HttpServletRequest object which will be used to obtain the request parameter, token-id

Output Parameters¶

the order ID that used in the particular payment transaction

Code Snippets¶

    Connection connection = createDbConnection("java:/DB2DS_USA");
    String orderId = "";
    try {
        orderId = PaymentUtils.queryAndPersistPaymentStatus(connection, request);
    } finally {
        if (connection != null) {
            connection.close();
        }
    }