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_jspService methiod calarification

vineet walia
Ranch Hand

Joined: Feb 16, 2008
Posts: 138
Code Source is scwcd study guide



why this out object is not available in _jspService. it is showing cnt resolve

Frits Walraven
Creator of Enthuware JWS+ V6
Bartender

Joined: Apr 07, 2010
Posts: 1522
    
  22

Hi Vineet,

You can override the jspInit() and jspDestroy() methods in a jsp, but you can't override the _jspService() method.

JSP.11.1.1.1 Protocol Seen by the JSP Page Author
....
In JSP 2.0 this is done by defining methods with the names jspInit and jspDestroy in a
declaration scripting element in the JSP page. The jspInit method, if present, will
be called to prepare the page before the first request is delivered. Similarly a JSP
container can reclaim resources used by a JSP page when a request is not being
serviced by the JSP page by invoking its jspDestroy method, if present.
A JSP page author may not (re)define servlet methods through a declaration
scripting element.

Regards,
Frits
Abimaran Kugathasan
Ranch Hand

Joined: Nov 04, 2009
Posts: 2066

vineet walia wrote:
why this out object is not available in _jspService. it is showing cnt resolve


How do you know that, the problem with out implicit object?


|BSc in Electronic Eng| |SCJP 6.0 91%| |SCWCD 5 92%|
vineet walia
Ranch Hand

Joined: Feb 16, 2008
Posts: 138
eclipse is showing that error ....
for me it is showing only... cnt resolve this object
Abimaran Kugathasan
Ranch Hand

Joined: Nov 04, 2009
Posts: 2066

vineet walia wrote:eclipse is showing that error ....
for me it is showing only... cnt resolve this object


As Frits indicated, you can't override _jspService() method.
vineet walia
Ranch Hand

Joined: Feb 16, 2008
Posts: 138
yes i go it
Abimaran Kugathasan
Ranch Hand

Joined: Nov 04, 2009
Posts: 2066

vineet walia wrote:yes i go it

So, is it the problem? Let's know it! Thanks!
Darryl Smith
Greenhorn

Joined: Aug 06, 2010
Posts: 5
You should not be overriding the _jspService method - The real problem.

Your problem is out is not declared. Why that happens is that when the JSP page is translated the JSP translator creates a _jspService method and then it starts initializing some of the implicit objects. One of the objects it instantiates is out.

Here is a snippet from the java file created by Tomcat 5.5



Have a look at line 10 and 22.
Seetharaman Venkatasamy
Ranch Hand

Joined: Jan 28, 2008
Posts: 5575

Darryl Smith is right! all the implicit objects are available with in service method of jsp. in other word, you can use implicit object only with <% %> and <%= %>.
and it is not possible with declaration(<%! %>)

As a side note: these scriptlets are obsolete.
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: _jspService methiod calarification
 
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