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NullPointer Exception using JDBC

Paras Ahuja
Ranch Hand

Joined: May 22, 2012
Posts: 62
Hi everyone,
i am encountring a very strange problem. I have two textfields tf[0] and tf[1] on a JFrame. Now, when anyone clicks on Ok button(again a component in my frame), the texts of the textfields are compared to values in an excel sheet. If the text entered in textfields already exist in the excel sheet, it generates error. Here is part of my code:


Now, the problem is: whenever i enter a value (already existing in the excel) in tf[1] ie. for Access IP, the code runs perfectly and it displays the error as its supposed to.
But when i enter a value (which is new and doesn't exist in excel) it generates following error:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
Excel shows the error occurs at the { after the following line:


Please help....

Darryl Burke
Bartender

Joined: May 03, 2008
Posts: 4523
    
    5

Break that up and add a debug sysout.


luck, db
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Paras Ahuja
Ranch Hand

Joined: May 22, 2012
Posts: 62
Thanks, but its still not working....
Do you know why the error is being generated?
Maneesh Godbole
Saloon Keeper

Joined: Jul 26, 2007
Posts: 9990
    
    7

Paras Ahuja wrote:Thanks, but its still not working....
Do you know why the error is being generated?

ItDoesntWorkIsUseless
Copy paste the full stack trace. The error indicates some variable is null.


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Rob Spoor
Sheriff

Joined: Oct 27, 2005
Posts: 19543
    
  16

Probably rs.getString(1) returns null.


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