Found out during an experiment today
In the jsp page , if it is <!-- --> to comment the code, the code can be commented so that it will not be run, but the service will still load it
Therefore, if there is an error in it or there is a logical error between the code in it and the execution code, an error will still be reported when the program is running.
So to avoid this from happening
We can use <%-- --%> to annotate the code in the jsp page, so that this situation can be avoided.