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Exception in thread "main" java.lang.NullPointerException

 
Greenhorn
Posts: 4
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Hi everybody Just wrote this script:


When I compile there are no errors.
But when i run i get this error:

Exception in thread "main" java.lang.NullPointerException
at Database.main(Database.java:29)


Dont understand why.
Tia,
Bram
 
Ranch Hand
Posts: 41
Eclipse IDE Ubuntu Linux
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bram van gemert wrote:
Hi everybody Just wrote this script:


When I compile there are no errors.
But when i run i get this error:

Exception in thread "main" java.lang.NullPointerException
at Database.main(Database.java:29)


Dont understand why.
Tia,
Bram



Is line 25 meant to be a useless while? It looks odd to me at that point. Are you missing curly braces?
 
Bartender
Posts: 4568
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The notes variable is initialized in the constructor. But no Database object is ever instantiated, so notes is still null. It's a static variable - why are you initializing it in a constructor?
 
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