POST is not idempotent

An HTTP GET is just for getting things, and it’s not

supposed to change anything on the server. So a GET

is, by definition (and according to the HTTP spec)

idempotent. It can be executed more than once

without any bad side effects.

POST is not idempotent—the data submitted in the

body of a POST might be destined for a transaction

that can’t be reversed. So you have to be careful with

your doPost() functionality!