问题:

How to create Payment Gateway using java?

Detailed Description for payment gateway in java (It will helpful for me). I want to integrate with my application.

回答1:

You don't want (and can't) implement a payment gateway. At least not by asking a question "how to create a payment gateway", and definitely not alone. What you are looking for, perhaps, is to be able to receive payments from customers. You can use an existing payment gateway:

PayPal
MoneyBookers
Authorize.net
WorldPay

All of them have well-described APIs and web-services to communicate with - just pick one with the best financial options for you and look for its documentation.

回答2:

If you mean integrating with an existing payment gateway (such as PayPal's) then you better read their official IPN documentation or a third party tutorial such as this (written for PHP but the logic is the same for all languages).

If this is a different payment gateway vendor, you need to find documentation and a tutorial.