Win a copy of Re-engineering Legacy Software this week in the Refactoring forum
or Docker in Action in the Cloud/Virtualization forum!
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic

Problem with logic:present

 
matt love
Ranch Hand
Posts: 67
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
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
Author and ninkuma
Marshal
Pie
Posts: 64629
86
IntelliJ IDE Java jQuery Mac Mac OS X
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Please be sure to ask Struts questions in the Struts forum. I have moved this post there for you.
 
Shankar Tanikella
Ranch Hand
Posts: 329
Eclipse IDE Java Oracle
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
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
 
matt love
Ranch Hand
Posts: 67
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Thanks Shankar for you reply.

What do you mean by "list size"?

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

Thanks.

Matt

 
Shankar Tanikella
Ranch Hand
Posts: 329
Eclipse IDE Java Oracle
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
"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.
 
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic