Warning: modified in the future

Question

I am getting the warning

Warning: sendmailpm.jsp modified in the future. 

What does this mean?

Answer 1

JSPs are compiled on-the-fly to servlets. The servlet container compares the "last modified" dates of both to see if the JSP has been changed and the servlet needs to be updated. A "last modified" date in the future indicates that something is wrong with the system clock, which is relevant because it could disrupt the abovementioned mechanism, leading to servlets that are not updated.