How to implement payment gateway in Java Struts project?

I want to implement a payment gateway in a开发者_运维问答 Java Struts project. What are the steps for this?

The generic steps for using a payment gateway in your site are:

1. Read the payment gateway reference documentation
2. Take the example application(s) provided by the payment gateway (if any)
3. Register, so that you obtain auth codes and be able to test
4. Create a prototype, based on the examples
5. Use the test environment of the payment gateway to check the correct working of your app
6. Switch to the real payment gateway for production

If you want to create a payment gateway like PayPal or WorldPay - don't. Too much experience and people are behind these systems.