I found on this forum how to redirect to another page in JSP. One of the respondents explained it perfectly.

Well you have two options. Either you’ll do a server side forward or a client side redirect.
Server side forward has no interaction with the browser and therefore the URL on the location bar won’t change.
But if you do the HTTP redirect, the browser is instructed to load the other page and the contents of the location will change.
It’s your call which one to choose.

forward:

<% if (s1.equals(s2) ) { %>

     <jsp:forward page="s2.jsp"/>

<% } %>

redirect:

<% if (s1.equals(s2) ) {

    response.sendRedirect("s2.jsp");

} %>