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Tag attributes and the setter method

Joseph Clark
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Joined: Sep 10, 2005
Posts: 48
I am trying to get the "Simple tag with attribute" example on page 511 of HFSJ working.

Here's the code . . .


The tag handler class and the bean are in $CATALINA_HOME/webapps/simple_tag/WEB-INF/classes/foo.

The .tld is in /WEB-INF.

When I run it, in Tomcat 5.5.12, I get a NullPointer exception at the line where the iterator is declared in the tag handler.

Any thoughts will be greatly appreciated.

Thank you,
Marc Peabody
pie sneak
Sheriff

Joined: Feb 05, 2003
Posts: 4727


Two big things here.
1) I don't think movieCollection.add("${movie1}"); will work because I don't think EL works inside of scriptlets.

2) <myTags:movieTag movieList="${movieCollection}"> won't find your collection because your never added it to any scope. Try ending the scriptlet with a:
request.setAttribute("movieCollection", movieCollection);
Fixing this second part alone will solve the NullPointer.


A good workman is known by his tools.
Chandra Sagi
Ranch Hand

Joined: May 05, 2005
Posts: 162
Two big things here.
1) I don't think movieCollection.add("${movie1}"); will work because I don't think EL works inside of scriptlets.

2) <myTags:movieTag movieList="${movieCollection}"> won't find your collection because your never added it to any scope. Try ending the scriptlet with a:
request.setAttribute("movieCollection", movieCollection);
Fixing this second part alone will solve the NullPointer.


I guess these should not be a problem.

Micheal,

I have given it a try but with no luck. I used



SimpleTagSupport to implement DynamicAttributes and also tried to add <dynamic-attributes> in tld. It was mentioned in HFJS on pg562 Q7. Try using this, may be it would solve your problem. Please let me know if you solve it.

Thanks
Chandu
Joseph Clark
Ranch Hand

Joined: Sep 10, 2005
Posts: 48
Well, this works . . .



Thanks for the tip Marc.
No telling when it would have occured to me to give the thing a scope.
[ March 03, 2006: Message edited by: Michael Clark ]
Chandra Sagi
Ranch Hand

Joined: May 05, 2005
Posts: 162
Marc,

No offense. You are correct. Could any of you explain me about Question 7 in HFJS on pg562.

Thanks in Advance.
Chandu
Joseph Clark
Ranch Hand

Joined: Sep 10, 2005
Posts: 48
I didn't get to dynamic att's yet, Chandu.

Did you read Bryan Basham's tutorial?:

http://www.coderanch.com/t/170429/java-Web-Component-SCWCD/certification/Tutorial-Dynamic-Attributes
 
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