i made three files ->javaservlet, xml and html xml file gives mapping, html takes one number as parameter and forwards it into javaservlet java servlet finds its square and prints it but in the browser when i enter a number and submit it the following error is shown HTTP Status 404 – Not Found Type… Read More Java Error when passing a value through html to a servlet but servlet not found. why?

I have generated a eight digit random OTP and sent it to mail using servlet. I want to validate the OTP at the next page without storing it anywhere like database and session. How can I do this? >Solution : This technique is done using the following steps: Create a cryptographic hash (HMAC) of the… Read More Validating a OTP without storing it anywhere like database and Sessions