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Thread: LinkedList with user defined types

  1. #1
    Super Moderator Norm's Avatar
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    May 2010
    Eastern Florida
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    Default Re: LinkedList with user defined types

    Exception in thread "main" java.lang.NullPointerException
    at inputintercase1.DataBase.toString(DataBase.java:42 ) (this is the line where iterator is created and initialized)
    at inputintercase1.InputIntercase1.main(InputIntercas e1.java:135)
    Look at line 42, find the variable with the null value and then backtrack to find out why that variable doesn't have a valid value.

    Please edit your post and wrap your code with
    to get highlighting and preserve formatting.
    If you don't understand my answer, don't ignore it, ask a question.

  2. #2
    Junior Member
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    Mar 2013
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    Default Re: LinkedList with user defined types

    Dear Norm
    Thanks for your reply, i found the bug, it was in the initialization of database object and object declaration.

    Thank you so much for your time

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