Practice Test Questions

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Practice
Test Questions


1
. A Java S
ervlet is running at ____________ site
.

2
. Method type ____________________

is the default HTTP request type?

3
.

URL of _______________

type request
can be bookmarked.

4
. _________________ request
objects are

passed to a Servlets
service()

method?

5
.
The _______________
object of an HTTP request can be shared by all requests in the same session.

6
.

The _______________
object of an HTTP session can be shared by all sessions in the same Web


application.

7
.

Servlet life cycle methods are ________, ________, ____________

8
. ___________ and ___________ are the two most often used method for an HTTP Servlet to retrieve


the request and respond to the request

9
.

Sketch out

a doPost() method signature.

10
.

The signature of setAttribute() method is ______________________________

11
.

The signature of getAttribute()

method is ______________________________

12
. How to use HttpServletRequest object to get value in a HTTP “input” parameters?

13
. Output a “Hello
World HTML” with Servlet code

14
. How a Servlet dispatches a request to another Web component with shared data?

15. Describe some

ways how a Web client can access a Java Servlet.

16. Sketch out

a Servlet code fragment to store a user name in a cookie.

17
.

Any HTML page can be converted to a JSP page by change its file extension to _______________

18
. ____________________ JSP tag can have Java statements.


19
. The att
ribute object of _______________

can be shared by all requests in the same session.

20
.

________________ JSP
action
tag
can also forward a control to a static HTML page

21
. A JSP file is
automatically re
-
compiled at the time

_________________________________

22
. ________________ translate
s

JSP
into its Servlet Java file
.

23
. How to ini
tialize a JSP life cycle and terminate it?

24
. How to access a JSP in a HTML form?

25. Sketch out a simple JS
P page which prompt for user name, says Hello <username>.

26. D
escribe how to use comments in JSP.

27
. What is JSP declaration element?

28
. What i
s JSP expression scripting element ?

29
. What is JSP page directive ?

30
. What is JSP scriptlets element
?



Answer Key


1. Server


2. GET


3. GET


4., ServletRequest


5. Request


6. Application


7
. init(), service(), destroy()

8
. doGet(), doPost()

9. vo
id

doPost( HttpServletRequest request, HttpServletResponse
response )



throws
ServletException, IOException;


10. public void
setAttribute
(java.lang.String

key,java.lang.Object

o)

//Stores an attribute in the context of this request. Attributes are

reset when the request is switched.


11. public Object
getAttribute
(String

name)

//Returns the value of the named attribute as an Object
.

12.

protected void doPost( HttpServletRequest request,


HttpServletResponse response )


throws S
ervle
tException, IOException


{


String feet = request.getParameter(“input” );


13. PrintWriter out = response.getWriter();



out.println( "<html><head><tit
le>Processing get requests with " +
"
data</title></head><body>
<h1>
Hello World</h1></body>
</html>" );


out.close(); // close stream to complete the page



}


14
. MyObject myObject = new MyObject(…)

request.setAttribute("myData", myObject);


RequestDispatcher rd;


rd = getServletContext().getRequestDispatcher(targetURL);


rd.forward(request, response);

.
. .

15. a.
Use an HTTP form. You can specify the HTTP Servlet in the action attribute of the <form> tag. The
default request type is the GET method. The POST method can also be specified in the method attribute.




b. For GET type HTTP requests you can also directly type
http://<host>/<servletName
> in the
URL location field of the browser if you don’t want to pass in any parameter values.


c. If you do need to pas
s in some parameter values with the request you can type
http://<host>/<servletName>?<paramterName>=<value
> such as
http://loc
alhost:8080/conv/conversion?feet=100
. There may be more then one pair of <parameter
name>/<value> which are separated by “&”. The “?” indicates the beginning of the query string.


d. Another way is to have a hyperlink tag

<A HREF=”http://<host>/<s
ervletName>Click me to get Servlet</A>


in

a HTML file so you can access the Servlet by clicking on the link. You can attach a query string to the
<servletName> in the hyper link tag.


16.
public class CookieServlet1 extends HttpServlet {




void do
Post( HttpServletRequest request,


HttpServletResponse response )


throws ServletException, IOException


{


String uname = request.getParameter( "username" );


Cookie cookie = new Cookie( “name”, uname );


Cookie.setMaxAge(5*6
0); //The cookie will expire in 5 minutes


response.addCookie( cookie );



out.println( " . . . " );


. . .


}


}

17.
jsp


18.
scriptlets


19. session

20.
<jsp:forward>


21
.

When the JSP
is changed

or

the JSP is accessed at first
time


22. JSP engine

23
.


<%! public void jspInit(){ . . . } %>


<%! public void jspDestroy(){ . . . } %>

24
.

<form action="/jsp/helloJsp.jsp">

...

</form>

25
.

<html>


<%
--

This is a Simple

JSP (comment from JSP tag
--

%>

<body>





Hello <%= request.getParameter("userName") %>!

<br>



</body>

</html>


26
.



<%
--

. . . %> is a JSP comment scripting element which



stays on the server.

27
. JSP declaration element <%! . . . %> which tells the JSP engine to insert the
enclosed java code into the


generated Servlet java source code somewhere outside of any method.

28
. The expression scripting element <%= . . . %> will display values of the enclosed expression in string


format

29
. The JSP page directive d
ire
cts the JSP engine to import the page

during the Servlet translation .

30
. JSP scriptlets are embedded within <% ...


%> tags. They are executed at the runtime.


The syntax is <% Java code


%>