SCWCD Questions 11-20

QUESTION NO: 11


Which two statements about tag files are true? (Choose two.)
A. Classic tag handlers and tag files CANNOT reside in the same tag library.
B. A file named foo.tag, located in /WEB-INF/tags/bar, is recognized as a tag file by the container.
C. A file named foo.tag, bundled in a JAR file but NOT defined in a TLD, triggers a container
translation error.
D. A file named foo.tag, located in a web application's root directory, is recognized as a tag file by
the container.
E. If files foo1.tag and foo2.tag both reside in /WEB-INF/tags/bar, the container will consider them
part of the same tag library.

Answer: B,E


QUESTION NO: 12


The sl:shoppingList and sl:item tags output a shopping list to the response and are used as
follows:
11. <sl:shoppingList>
12. <sl:item name="Bread" />
13. <sl:item name="Milk" />
14. <sl:item name="Eggs" />
15. </sl:shoppingList>
The tag handler for sl:shoppingList is ShoppingListTag and the tag handler for sl:item is
ItemSimpleTag.
ShoppingListTag extends BodyTagSupport and ItemSimpleTag extends SimpleTagSupport.
Which is true?

A. ItemSimpleTag can find the enclosing instance of ShoppingListTag by calling getParent() and
casting the result to ShoppingListTag.
B. ShoppingListTag can find the child instances of ItemSimpleTag by calling super.getChildren()
and casting each to an ItemSimpleTag.
C. It is impossible for ItemSimpleTag and ShoppingListTag to find each other in a tag hierarchy
because one is a Simple tag and the other is a Classic tag.
D. ShoppingListTag can find the child instances of ItemSimpleTag by calling getChildren() on the
PageContext and casting each to an ItemSimpleTag.
E. ItemSimpleTag can find the enclosing instance of ShoppingListTag by calling
findAncestorWithClass() on the PageContext and casting the result to ShoppingListTag.

Answer: A


QUESTION NO: 13


Servlet A receives a request that it forwards to servlet B within another web application in the
same web container. Servlet A needs to share data with servlet B and that data must not be visible
to other servlets in A's web application. In which object can the data that A shares with B be
stored?
A. HttpSession
B. ServletConfig
C. ServletContext
D. HttpServletRequest
E. HttpServletResponse

Answer: D


QUESTION NO: 14


Your web site has many user-customizable features, for example font and color preferences on
web pages. Your IT department has already built a subsystem for user preferences using the Java
SE platform's lang.util.prefs package APIs, and you have been ordered to reuse this subsystem in
your web application. You need to create an event listener that constructs the preferences factory
and stores it in the application scope for later use. Furthermore, this factory requires that the URL
to a database must be declared in the deployment descriptor like this:
42. <context-param>
43. <param-name>prefsDbURL</param-name>
44. <param-value>
45. jdbc:pointbase:server://dbhost:4747/prefsDB
46. </param-value>

47. </context-param>
Which partial listener class will accomplish this goal?
A. public class PrefsFactoryInitializer implements ContextListener {
public void contextInitialized(ServletContextEvent e) {
ServletContext ctx = e.getContext();
String prefsURL = ctx.getParameter("prefsDbURL");
PreferencesFactory myFactory = makeFactory(prefsURL);
ctx.putAttribute("myPrefsFactory", myFactory);
}
// more code here
}
B. public class PrefsFactoryInitializer implements ServletContextListener {
public void contextCreated(ServletContext ctx) {
String prefsURL = ctx.getInitParameter("prefsDbURL");
PreferencesFactory myFactory = makeFactory(prefsURL);
ctx.setAttribute("myPrefsFactory", myFactory);
}
// more code here
}
C. public class PrefsFactoryInitializer implements ServletContextListener {
public void contextInitialized(ServletContextEvent e) {
ServletContext ctx = e.getServletContext();
String prefsURL = ctx.getInitParameter("prefsDbURL");
PreferencesFactory myFactory = makeFactory(prefsURL);
ctx.setAttribute("myPrefsFactory", myFactory);
}
// more code here
}
D. public class PrefsFactoryInitializer implements ContextListener {
public void contextCreated(ServletContext ctx) {
String prefsURL = ctx.getParameter("prefsDbURL");
PreferencesFactory myFactory = makeFactory(prefsURL);
ctx.putAttribute("myPrefsFactory", myFactory);
}
// more code here
}

Answer: C



QUESTION NO: 15


A developer wants a web application to be notified when the application is about to be shut down.
Which two actions are necessary to accomplish this goal? (Choose two.)
A. include a listener directive in a JSP page
B. configure a listener in the TLD file using the <listener> element
C. include a <servlet-destroy> element in the web application deployment descriptor
D. configure a listener in the application deployment descriptor, using the <listener> element
E. include a class implementing ServletContextListener as part of the web application deployment
F. include a class implementing ContextDestroyedListener as part of the web application
deployment
G. include a class implementing HttpSessionAttributeListener as part of the web application
deployment

Answer: D,E


QUESTION NO: 16


You want to create a filter for your web application and your filter will implement
javax.servlet.Filter.
Which two statements are true? (Choose two.)
A. Your filter class must implement an init method and a destroy method.
B. Your filter class must also implement javax.servlet.FilterChain.
C. When your filter chains to the next filter, it should pass the same arguments it received in its
doFilter method.
D. The method that your filter invokes on the object it received that implements
javax.servlet.FilterChain can invoke either another filter or a servlet.
E. Your filter class must implement a doFilter method that takes, among other things, an
HTTPServletRequest object and an HTTPServletResponse object.

Answer: A,D


QUESTION NO: 17


Which three are true about the HttpServletRequestWrapper class? (Choose three.)
A. The HttpServletRequestWrapper is an example of the Decorator pattern.
B. The HttpServletRequestWrapper can be used to extend the functionality of a servlet request.
C. A subclass of HttpServletRequestWrapper CANNOT modify the behavior of the getReader
method.

D. An HttpServletRequestWrapper may be used only by a class implementing the
javax.servlet.Filter interface.
E. An HttpServletRequestWrapper CANNOT be used on the request passed to the
RequestDispatcher.include method.
F. An HttpServletRequestWrapper may modify the header of a request within an object
implementing the javax.servlet.Filter interface.

Answer: A,B,F


QUESTION NO: 18


Click the Exhibit button.
The resource requested by the RequestDispatcher is available and implemented by the
DestinationServlet.
What is the result?

A. An exception is thrown at runtime by SourceServlet.
B. An exception is thrown at runtime by DestinationServlet.
C. Only "hello from dest" appears in the response output stream.
D. Both "hello from source" and "hello from dest" appear in the response output stream.

Answer: A


QUESTION NO: 19


A developer wants to make a name attribute available to all servlets associated with a particular
user, across multiple requests from that user, from the same browser instance.
Which two provide this capability from within a tag handler? (Choose two.)

A. pageContext.setAttribute("name", theValue);
B. pageContext.setAttribute("name", getSession());
C. pageContext.getRequest().setAttribute("name", theValue);
D. pageContext.getSession().setAttribute("name", theValue);
E. pageContext.setAttribute("name", theValue,
PageContext.PAGE_SCOPE);
F. pageContext.setAttribute("name", theValue,
PageContext.SESSION_SCOPE);

Answer: D,F


QUESTION NO: 20


Given the definition of MyServlet:
11. public class MyServlet extends HttpServlet {
12. public void service(HttpServletRequest request,
13. HttpServletResponse response)
14. throws ServletException, IOException {
15. HttpSession session = request.getSession();
16 session.setAttribute("myAttribute","myAttributeValue");
17. session.invalidate();
18. response.getWriter().println("value=" +
19. session.getAttribute("myAttribute"));
20. }
21. }
What is the result when a request is sent to MyServlet?
A. An IllegalStateException is thrown at runtime.
B. An InvalidSessionException is thrown at runtime.
C. The string "value=null" appears in the response stream.
D. The string "value=myAttributeValue" appears in the response stream.

Answer: A