All about tony lee

strange output !! include / jsp:include

hi,
i guess the code of C.jsp is inserted into B.jsp whose code is eventually added into A.jsp. System.out.println("THIS METHOD CALLED ") is executed for two times?
I'm confused here

22 years ago

Web Component Certification (OCEJWCD)

endcodeURL vs encodeRedirectURL

Hi,
Could someone tell me what the difference between
HttpServletResponse.endcodeURL and HttpServletResponse.endcodeRedirectURL ?

22 years ago

Web Component Certification (OCEJWCD)

confused with jsp result

Hi,
I need a help. The following is a question:

what will be printed out by the following part of a jsp page?
<prefix:sufix>
Hello
</prefix:sufix>
1) The tag handler won't compile.
2) The jsp page will print Hello how are you?
3) The jsp page will print how are you? Hello
4) The jsp page will print Hello
Answer is 4.
Could someone try it on your machine? I tried and found the right answer should be 1

avax.servlet.ServletException: Since tag handler class util.body does not implement BodyTag, it can't return BodyTag.EVAL_BODY_TAG ...

Thanks,

22 years ago

Web Component Certification (OCEJWCD)

Bean Scope

Hi,
I tried this code, and it runs fine. If you want to print a note, please try this:

22 years ago

Web Component Certification (OCEJWCD)

TagSupport vs TagBodySupport

Hi friends,
I tried two handler classes: One implementing TagBodySupport and another TagSupport.
code 1

code 2

The JSP file including code:
<utile:my>
Hello
</utile:my>
With code 1, browser print Hello
With code 2, there's an exception like
javax.servlet.ServletException: (class: org/apache/jsp/$2_0005f5$jsp, method: _jspService signature: (Ljavax/servlet/http/HttpServletRequest;Ljavax/servlet/http/HttpServletResponse V) Incompatible object argument for function call ...
Could someone tell me why?
Thanks,

22 years ago

Web Component Certification (OCEJWCD)

can someone explain me the output for the code

The default doStartTag() returns EVAL_BODY_BUFFERED.

I tried by adding a doStartTag() which returns EVAL_BODY_INCLUDE, then it print "Hello how are you." We can find the return value matters.
What does EVAL_BODY_BUFFERED mean

22 years ago

Web Component Certification (OCEJWCD)

Session Listeners

Hi,
The difference is that HttpSessionBindingListener can be implemented to notify any object, while HttpSessionAttributeListener is only used for attribute list.

22 years ago

Web Component Certification (OCEJWCD)

a qustion on jsp

Given the following tag handler defined with <bodycontent>JSP</bodycontent>
public class body extends TagSupport {
public int doStartTag() throws JspException{
return EVAL_BODY_INCLUDE;
}
public int doAfterBody() throws JspException {
try { pageContext.getOut().print("how are you?"); }catch(IOException e) {}
return SKIP_BODY;
}
}
what will be printed out by the following part of a jsp page?
<prefix:sufix>
Hello
</prefix:sufix>
1) The tag handler won't compile.
2) The jsp page will print Hello how are you?
3) The jsp page will print how are you? Hello
4) The jsp page will print Hello
The answer is 3. I think it should be 2

22 years ago

Web Component Certification (OCEJWCD)

a qustion on handler class

Hi,
Is anybody know which methods - doStartTag(), doEndTag(), doBodyTag(), are mandatory to a handler class? Why?
Thanks,

22 years ago

Web Component Certification (OCEJWCD)

question from jsp spec

I have problems with nested stuff

, like nested scripting, nested actions, ...
Could anyone tell me about the principle there?

22 years ago

Web Component Certification (OCEJWCD)

events on startup of webapp

Hi,
It's my version:
On startup of webapp
##load the servlet class
##instantiate the class
##call init
##call contextInitialized - if ServletContextListeners is declared in DD.
when there is a request
##call service -> (doGet, doPost)
##HttSession ses = request.getSession() - use the existing session or create one if necessary.
##call sessionCreated() - if the class implement HttpSessionListener.
##call sessionDidActivate() - if the class implement HttpSessionActivationListener.
##call other listener methods if any session listener interfaces are implemented.
on shutdown
##destroy
##sessionDestroyed, sessionWillPassivate? ..
##contextDestroyed
Sorry, I just add on the author's message.

22 years ago

Web Component Certification (OCEJWCD)

Passed with 88%

Hi Andy,
You gave a few interesting examples. Thanks.

for 2. How about I give an example of useBean scope:
<% { %>
<jsp:useBean id=test ..../>
....
<% } %>
....
will the test bean outside the { } scope.

In the case I think the test bean is only available to the local {}, no mater what scope has been declared, right?

for 3. I don't think the session.invalide() will call when we shut down the web-app, instead HttpSessionActivationListener.willPassivate() will call.

Shall we need to impliment HttpSessionActivationListener manually, or container automatically does that for us?

for 4. can we do something like this:
<jsp:useBean id= .... value='<eg:egtag attr="test"/>'/>

I know we can use a request time attribute value like "<%= scriptlet_expr %>" or '<%= scriptlet_expr %>'. Could we use custom tag expression

Whenever we use sigle quotes or double quotes, I think the principle is making no intersections of the quotes, right?
In this way, '..".."..' is equivalent to "..'..'.."

22 years ago

Web Component Certification (OCEJWCD)

a qstn

Given:
<jsp:useBean id="temp"
class="java.lang.String" />
<% temp="temp";
out.println(temp); %>
What is the output?
A) temp
B) empty
C) ServletException
D) null
A is correct choice.
I think var temp in <% temp="temp";
out.println(temp); %> is not defined. How does it work

22 years ago

Web Component Certification (OCEJWCD)

wrong with my tomcat

Could you be more specific about your problem, error codes

The problem is:
When I type in http://localhost:8080/my.html into the browser, a window "Unknown File Type" is prompted. But I can open my.html as a common file

Thanks,

22 years ago

Web Component Certification (OCEJWCD)

wrong with my tomcat

Hi guys,
I don't know why my tomcat4.0 doesn't work well:
I can't read html files from browser.
It used to do well, but not now. Anyway, it still is fine with jsps and servlets.
Could someone tell me why?
Thanks,

22 years ago

Web Component Certification (OCEJWCD)

tony lee

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