NullPointerException with outgoingEdgeSetOf

[acbart]

I believe this is being caused by trying to access the outgoingEdgeSetOf of a vertex that has no neighbors. So something like:

GraphAdjList<String, Room, Connection> graph = new GraphAdjList<>();
graph.addVertex("Alpha", room);
graph.outgoingEdgeSetOf("Alpha");

[acbart]

Or perhaps, more accurately, it's returning null in that case, and I was dereferencing it later on. Either way, not necessarily the behavior I expected for this helper function. But makes sense I suppose.

[krs-world]

The method should be returning an iterable object  that should make it easy to modify the edge's properties. Check the graph adjacency list tutorial. This should avoid this issue..

http://bridgesuncc.github.io/tutorials/Graph_AL.html

If its not doing that, let us know.

    -- krs

On 4/1/20 7:10 AM, Austin Cory Bart wrote:

Or perhaps, more accurately, it's returning null in that case, and I was dereferencing it later on. Either way, not necessarily the behavior I expected for this helper function. But makes sense I suppose.

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[acbart]

Ah, then yes I think this is misbehaving. I think you need to add if (graph.getAdjacencyList(vertex) != null) { around it in case there are no adjacent nodes.

[AlecGoncharow]

You are correct, this should not happen. Will push a fix soon.