www 4-7

Match the method getContextPath to the following classes or interfaces

Which types of objects are available to the jspInit() method?

Which are true about the RequestDispatcher interface?

Which method of HttpServletResponse is used to redirect an HTTP request to another URL?

Which is most logically stored as an attribute in session scope?

Given:
1. import javax.servlet.http.*;
2. public class MySessionListener
implements HttpSessionListener {
3. public void sessionCreated() {
4. System.out.println(“Session Created”);
5. }
6. public void sessionDestroyed() {
7. System.out.println(“Session Destroyed”);
8. }
9. }
What is wrong with this class?

Which statements about session tracking are true?

Match the method getAttribute to the following classes or interfaces

Which types of objects can store attributes?

Which of the following are NOT listener event types in the J2EE 1.4 API?

What is the recommended way to deal with servlets and thread safety?

Given a session object s with two attributes named myAttr1 and myAttr2, which will remove both attributes from this session?

If a servlet is invoked using the forward or include method of RequestDispatcher, which methods of the servlet’s request object can access the request attributes set by the container?

Given this DD element:
47.
48. *.jsp
49. true
50.
What does the element accomplish?

Which of the following methods are declared in HttpServletRequest as opposed to in ServletRequest?

When declaring a listener in the DD, which sub-elements of the element are required?

Given a session object s, and the code:
s.setAttribute(“key”, value);
Which listeners could be notified?

Choose the servlet code fragment that gets a binary stream for writing an image or other binary type to the HttpServletResponse.

Which directives specify an HTTP response that will be of type “image/svg”?

Which statements about HttpSession objects are true?

Given this code from an otherwise valid HttpServlet that has also been
registered as a ServletRequestAttributeListener:
10. public void doGet(HttpServletRequest req,
HttpServletResponse res)
11. throws IOException, ServletException {
12. req.setAttribute(“a”, “b”);
13. req.setAttribute(“a”, “c”);
14. req.removeAttribute(“a”);
15. }
16. public void attributeAdded(ServletRequestAttributeEvent ev) {
17. System.out.print(“ A:” + ev.getName() + “->” + ev.getValue());
18. }
19. public void attributeRemoved(ServletRequestAttributeEvent ev) {
20. System.out.print(“ M:” + ev.getName() + “->” + ev.getValue());
21. }
22. public void attributeReplaced(ServletRequestAttributeEvent ev) {
23. System.out.print(“ P:” + ev.getName() + “->” + ev.getValue());
24. }

Which statements about session timeouts are true?

How would you use the HttpServletResponse object in a servlet to add a cookie to the client?

Which method(s) can be used to ask the container to notify your application whenever a session is about to timeout?

Given req is a HttpServletRequest, which gets a binary input stream?

How should servlet developers handle the HttpServlet’s service() method when extending HttpServlet?

Which HTTP methods are NOT considered idempotent?

Given this JSP:
1. <%@ page import=”java.util.*” %>
2. The people who like
3. <%= request.getParameter(“hobby”) %>
4. are:

5. <% ArrayList al = (ArrayList) request.getAttribute(“names”); %>
6. <% Iterator it = al.iterator();
7. while (it.hasNext()) { %>
8. <%= it.next() %>
9.

10. <% } %>
11.
Which types of code are used in this JSP?

Which statements about RequestDispatcher are true (where applicable, assume the RequestDispatcher was not obtained via a call to getNamedDispatcher())? (

When using a RequestDispatcher, the use of which methods can often lead to an IllegalStateException?

Which statements about listeners are true?

Choose the servlet code fragment that would retrieve from the request the value of a cookie named “ORA_UID”?

Match the method getCookies to the following classes or interfaces

Which statements about ServletContext initialization parameters are true?

Which statements about HttpSession objects in distributed environments are true?

How would you set a header named “CONTENT-LENGTH” in the HttpServletResponse object?

Given:
<%@ page isELIgnored=”true” %>
What is the effect?

Which are true?

Which interfaces define a getSession() method?

Which statements about session attributes are true?

Which methods are used by a servlet to handle form data from a client?

Which statements about jspInit() are true?

Given:
10. public class MyServlet extends HttpServlet {
11. public void doGet(HttpServletRequest request,
HttpServletResponse response)
12. throws IOException, ServletException {
13. // request.getSession().setAttribute(“key”, “value”);
14. // request.getHttpSession().setAttribute(“key”, “value”);
15. // ((HttpSession)request.getSession()).setAttribute(“key”, “value”);
16. // ((HttpSession)request.getHttpSession()).setAttribute(“key”, “value”);
17. }
18. }
Which line(s) could be uncommented without causing a compile or runtime error?

How would servlet code from a service method (e.g., doPost() ) retrieve the value of the “User-Agent” header from the request?

Which types define the methods getAttribute() and setAttribute()?

Given that req is an HttpServletRequest, which snippets create a session if one doesn’t exist?

Which calls provide information about initialization parameters that are applicable to an entire web application?

If a client will NOT accept a cookie, which session management mechanism could the web container employ?

Which HTTP methods are used to show the client what the server is receiving?

Given:
13. public class ServletX extends HttpServlet {
14. public void doGet(HttpServletRequest req, HttpServletResponse resp)
15. throws IOException, ServletException {
16. HttpSession sess = new HttpSession(req);
17. sess.setAttribute("attr1", "value");
18. sess.invalidate();
19. String s = sess.getAttribute("attr1");
20. }
21. }
What is the result?