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list ADTs

 
tom eustace
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hi all,
been having a problem which for the life of me i can't figure out. The assignment requires the use of a doubly linked list ADT, but i keep getting a NullPointerException which i don't understand, chances are its something silly which i'm just not seeing well at least i hope it is. Heres what i've got, i've tracked the bug to the insertAfterCurrent() method, there are other methods that might have problems aswell and some that are downright silly, but one step at a time.

thanks for any help
later
y'all.
 
Jeff Langr
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You should post a short piece of client (testing) code that demonstrates the problem.
-Jeff-
 
tom eustace
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ok, i should have done so before. so here is some test code that throws the NullPointerException.

For my assignment i need to be able to create possible many lists and manipulate them. Hence this line which i think is where the problem starts
but the debugger points to the insertAfterCurrent() method and the second.setPrev(after_current); line specifically.
once again thanks for any halp
t
 
Jeff Langr
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I think in your test you don't want to advance after an insertion:

And offEnd seems like it should be:

-Jeff-
 
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