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Perpared Statemt is throwing NullPointerException after getting context from ServletContextListener?  RSS feed

 
Anuj Kalra
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Posts: 10
Java Oracle Tomcat Server
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Hello!
So I have a Listener that implements ServletContextListener. in the contextInitialized method that makes a database connection with Oracle 11g schema.

After establishing a database connection in the listener (I do get a successful println that I wrote in case the connection was made), I set Attributes to a servletcontext


In my jsp file under a scriplet tag I make an instance of the Connection interface and initialize it with context's attribute:


So in the output i am getting "Connection Made" but i am getting a NullPointerException from the Prepared Statement line; (I am not getting "preparedstatement created" in the output.

Why is this prepared statement causing problems?
Please Help!
 
Paul Clapham
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Shouldn't you be using the getAttribute method here? After all you used setAttribute to put the connection into the application context.
 
Anuj Kalra
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Java Oracle Tomcat Server
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Paul Clapham wrote:Shouldn't you be using the getAttribute method here? After all you used setAttribute to put the connection into the application context.


You are right; it works now!
I feel like such an idiot :
application is the implicit variable for ServletContext in JSP and i was calling getContext() from it..
It works perfectly fine now!

Thanks so much Mr. Paul; I was stuck on this for 2 days but I can continue with my work finally.

Head First People were so right; You people here are just AMAZING!!!
 
J. Kevin Robbins
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That doesn't look like a good design to me. If you are opening a connection in the listener then that connection is going to stay open until the application shuts down; it will never be returned to the connection pool. Connections should be opened in the DAO object and then closed as soon as possible.
 
It is sorta covered in the JavaRanch Style Guide.
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