December 2003
Intermediate to advanced
764 pages
24h 58m
English
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Checking for a Valid Session
Authentication is only half of the solution. We must also add access control to each page in the application. Example 13-4 shows the main.jsp page as an example of a protected page. This page shows all messages for the projects of the user’s choice. It also has a form with which the user can change the list of projects of interest and links to a page for posting new messages, and to log out.
Example 13-4. A protected JSP page (main.jsp)
<%@ page contentType="text/html" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
<%-- Verify that the user is logged in --%>
<c:if test="${validUser == null}">
<jsp:forward page="login.jsp">
<jsp:param name="origURL" value="${pageContext.request.requestURL}" />
<jsp:param name="errorMsg" value="Please log in first." />
</jsp:forward>
</c:if> <html> <head> <title>Project Billboard</title> </head> <body bgcolor="white"> <h1>Welcome ${fn:escapeXml(validUser.firstName)}</h1> Your profile currently shows you like information about the following checked-off projects. If you like to update your profile, make the appropriate changes below and click Update Profile. <form action="updateprofile.jsp" method="post"> <c:forEach items="${validUser.projects}" var="current"> <c:choose> <c:when test="${current == 'JSP'}"> <c:set var="jspSelected" value="true" /> </c:when> <c:when test="${current == 'Servlet'}"> <c:set var="servletSelected" value="true" ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.