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How to get to the custom tags on a page from a scriptlet?

Jesper de Jong
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Joined: Aug 16, 2005
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My colleague has an ASPX page that contains server controls (the equivalent of custom tags in a JSP page). In this page, he has a scriptlet (in C#) that looks up one of the server controls on the page by ID, and then calls a method on it. It looks like this:

So, converted to Java / JSP terminology: he has a scriptlet that looks up a custom tag on the page according to its Id attribute, and then calls a method on the tag handler object for that custom tag.

Is something like this possible when using JSPs?

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David Newton
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Ewwwwww.

But as far as I know, this isn't possible: the structure of ASP and JSP pages is different; ASP pages are more component-oriented. It'd probably be possible if you were using a component-based page/tag rendering system, but if it's action-based, probably not. The JSP is rendered into a servlet, which is just making function calls to the tag--you'd have to demangle the tag names/instances, and even then, I don't know if it'd work.
Jesper de Jong
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Joined: Aug 16, 2005
Posts: 14074
    
  16

Thanks. Yes, this looked strange to me too, and you probably can't (easily) do the same kind of thing using JSPs. He'll have to find some other way to solve his problem.
Kris Schneider
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Joined: Feb 14, 2001
Posts: 71
Maybe I'm missing something, but how is this much different than:



I guess the point is to think about using beans instead of tags/actions. Is there a reason for requiring a tag? Of course, servlets and filters are other options...
David Newton
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Because a bean isn't a user-interface component.
Kris Schneider
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Posts: 71
David Newton wrote:Because a bean isn't a user-interface component.


So, if I used the Struts bean tag instead then it would be a UI component?

Edit: Just goes to show how much that response made my eyes cross, because, you know, <jsp:useBean> really is a tag...
David Newton
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No, bean tags aren't UI components either.
Kris Schneider
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Joined: Feb 14, 2001
Posts: 71
David Newton wrote:No, bean tags aren't UI components either.


Got it - this is a "know 'em when I see 'em kind of thing". So, do we know that <prefix:Query> is more like a bean tag or more like a UI component...however that's defined...
 
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