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B-Tree implementation
Hi, i have passed my exam from java programming, but i have to solve one more homework. Its about B-tree implementation :/ i dont really know, how to do it. I have a few lines of code but its no working properly.
When i define the number of keys in node, i can add them, but if i add one more key, there is a null.pointer.exception. And with remove method i dont know
Here is a task and my code.
B-tree homework.txt
Attachment 1736
Related threads:
Re: B-Tree implementation
Please post any questions you have and the code here on the forum.
Please copy the full text of the error messages and past it here.there is a null.pointer.exception.
If you don't understand my answer, don't ignore it, ask a question.
Re: B-Tree implementation
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1
at java.util.ArrayList.elementData(ArrayList.java:371 )
at java.util.ArrayList.get(ArrayList.java:384)
at Node.getChild(Homework6.java:151)
at Node.splitChild(Homework6.java:117)
at Tree.add(Homework6.java:32)
at Main.main(Homework6.java:193)
Java Result: 1
Re: B-Tree implementation
At line 151 the code calls the get() method with an invalid value of -1. Look at that line and see why the value is -1 and then backtrack in the code to see why the value is not a valid one.Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1
at java.util.ArrayList.elementData(ArrayList.java:371 )
at java.util.ArrayList.get(ArrayList.java:384)
at Node.getChild(Homework6.java:151)
If you don't understand my answer, don't ignore it, ask a question.
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