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JTabbedPane.setTitleAt not working  RSS feed

 
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I've got a small method which I want to iterate through a JTabbedPane and String [] to set the title:



However, with this I get the error NullPointerException:



Line 43 is the tabbedPane.setTitleAt - the tabbedPane is there and it has 11 tabs - so why would I get NullPointerException?
TIA
Adam
 
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Post a SSCCE.
 
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The exception ends at that line, so that means that on that line something before a . or array access is null. There is only one culprit: tabbedPane.
 
Adam Cripps
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Thanks.

tabbedPane has an instance which has tabs - am I thinking that this doesn't work correctly? This is how I set the constructor up:

 
Rob Spoor
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Adam Cripps wrote:


That's an often made error. You did not initialize your instance variable but have instead created a local variable that shadows the instance field. This local variable is initialized. Simply remove the type declaration of that local variable and you will use the instance variable instead.
 
Adam Cripps
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The proverbial "D'Oh!" - many thanks.
 
Rob Spoor
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You're welcome.
 
It is sorta covered in the JavaRanch Style Guide.
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