#155 OrderedKAryTree - wrong constructor argument or?

[Anonymous]

Don\'t know if it\'s a bug, but can\'t add any Edge/Childs after creating OrderedKAryTree with \"2\" argument while making an object.

OrderedKAryTree tree = new OrderedKAryTree(2);
tree.addVertex(parent);
tree.addEdge(\"Edge parent->child\", parent, child, 0);

Where parent and child are intances of my class MusicItem (doesn\'t matter what it is).

Exception in thread \"main\" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.RangeCheck(ArrayList.java:547)
at java.util.ArrayList.get(ArrayList.java:322)
at edu.uci.ics.jung.graph.OrderedKAryTree.addEdge(OrderedKAryTree.java:236)
at JUNG.Main.main(Main.java:30)
Java Result: 1

Please answer (lukasz.modlinski@gmail.com)

[Susanta Tewari]

Yep, I faced the same problem and I believe it is a bug after checking the source code around OrderedKAryTree.java:236. Also, the method where you do not have to provide the child index is not properly implemented.

[Tom Nelson]

the code calls new ArrayList(2), which creates an ArrayList of size 0, despite having initial capacity of 2. Accessing the element at index 0 of a List of size 0 causes the out of bounds exception.

[Susanta Tewari]

If line 232 is modified from

outedges = new ArrayList<E>(this.order);

to

outedges = new ArrayList(Collections.nCopies(this.order, null));

it might clear this bug.