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Java lang NullPointerException error

Anand Karia
Ranch Hand

Joined: Sep 25, 2004
Posts: 156

Below is the function that i m using on two scnerio.

1st Scnerio.
Just click on add button make entry into required fields and click Save Button.

I call this function before saving data into database. If i am calling this function within the form (Class A) then it is working fine and good.

2nd Scnerio
I have 3 classes i.e. Class A, Class B and Class C

While working on Class A i am calling Class B and filling all kind of required data from Class B to global vector in Class C. After setting data from Class B to another Class C via vector, I close down Class B and again going to Class A as it is already opened.

On clicking a single button in Class A to fill my JTable from Class C (Vector), my all data is appearing and working fine.

But while saving as the below function is called i got an error on "Statement" statement i.e. Java.lang.NullPointerException.

This is not printed.

Can any one tell me why I am getting this error as the same is working in 1st Scnario.

Love is GOD and GOD is Love.
Anand Karia
IT Concretor.......
M/s. Anand Karia Concreting IT
Keith Lynn
Ranch Hand

Joined: Feb 07, 2005
Posts: 2398
It looks the problem may be with your connection.


Before you try that line, try printing cnnd with System.out.println(cnnd) to see if it's null.
Stefan Wagner
Ranch Hand

Joined: Jun 02, 2003
Posts: 1923

It's generally a bad practise to catch any unspecific Exception:

Instead catch specific (SQL...) Exceptions.
Anand Karia
Ranch Hand

Joined: Sep 25, 2004
Posts: 156

Thanks Keith Lynn

You were right. Problem was there. I mistakenly close the connection from Class C.

Thanks anyway.

javascript: x()
javascript: x()
I agree. Here's the link:
subject: Java lang NullPointerException error
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