Online payment on the Java Web

/**----------------------Java Online payment-------------------------------------
1. Create a Web project
2. Create a front-end payment page form
3. Import the payment platform Port class jar
4. Create a class to read the user's platform account key
5. Create a servlet
6. (key) Request.getparameter to obtain payment information for the corresponding platform
7. (focus) Reference platform class provides methods for HMAC encryption of transaction data
8. (key) Request.setattribute () Send the platform payment information to the transfer page
9. (focus) Create a Transfer page to confirm the payment information required to submit all platforms
10. Create a servlet
11. (focus) Request.getparameter get platform return payment information
12. (focus) Reference platform class provides methods for HMAC decryption of transaction data
13. Return the payment result to the page True/false
*/

Online payment on the Java Web