[jgrapht-developers] Edge vertex types

[Charles F. <cf...@us...>]

Hi,

I am getting an error when compiling the following block of code:

public class NeighborIndex<V, E extends Edge<V>> implements GraphListener<V, E>
{
   public void edgeAdded(GraphEdgeChangeEvent<V, E> e)
   {
       E edge = e.getEdge();
       V source = edge.getSource();
   }
}

The error is:

   incompatible types
   found   : java.lang.Object
   required: V
           V source = edge.getSource();
                                    ^

My understanding of generics suggests that the compiler should have
already known that E extends Edge<V>, and should thus have expected V
instead of Object in the above block of code. Obviously I was wrong. Any
suggestions as to what I am missing, and how I can fix this?

thanks,
Charles

-- 
Half a pound
For
Half a buck
Come on shavers
You're in luck
Burma-Shave
http://burma-shave.org/jingles/1931/half_a_pound