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Java lang NullPointerException error

 
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Posts: 158
Java
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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.

System.out.println("Test");
This is not printed.

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

 
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It looks the problem may be with your connection.

cnnd.myDetailCon.

Before you try that line, try printing cnnd with System.out.println(cnnd) to see if it's null.
 
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Scala Postgres Database Linux
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It's generally a bad practise to catch any unspecific Exception:


Instead catch specific (SQL...) Exceptions.
 
Anand Karia
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Thanks Keith Lynn

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

Thanks anyway.

javascript: x()
javascript: x()
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