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Problem with logic:present

matt love
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Joined: Jan 25, 2010
Posts: 67
I've condensed the code to its barest essentials to illustrate my problem as clearly as I can.

My addAssignment.jsp is showing the header "Messages" when the LinkedList should be, and appears to be, empty. If there are no messages in the LinkedList, I expect the logic:present tag to preclude the printing of the header "Messages". How do I prevent the header "Messages" from printing if there are no messages in the LinkedList?

The struts-config file.

The LoginAction file illustrates how I use the LinkedList. Also, the LoginAction works correctly with the Login.jsp page, the LinkedList and the Logic and Bean tags. That is, when error messages were present in the LinkedList, the Login.jsp page showed them corretly under the header Messages.

Bear Bibeault
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Joined: Jan 10, 2002
Posts: 60782

Please be sure to ask Struts questions in the Struts forum. I have moved this post there for you.

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Shankar Tanikella
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Joined: Jan 30, 2011
Posts: 329

Hi Matt,
Hope this issue is already solved. If not, Logic present would return true if the specified attribute is present in the scope mentioned (in your case it is "messages" in scope "request"). So you could use list size/logic:empty to identify empty lists to display your header

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matt love
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Joined: Jan 25, 2010
Posts: 67
Thanks Shankar for you reply.

What do you mean by "list size"?

Are you referring to java code like: int x = listName.size();



Shankar Tanikella
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Joined: Jan 30, 2011
Posts: 329

"Perfectly yes" when we talk about the logic behind it. But to implement the "same" you would use scriplets. However, never use such code in your JSP's. Struts equivalent would be something like OR if not sure about this use bean define to capture the size and work in similar fashion.
I agree. Here's the link: http://aspose.com/file-tools
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