[jgrapht-users] strange output when running the example from [https://github.com/jgrapht/jgrapht/wiki/LabeledEdges]

[Jim - FooBar(); <jim...@gm...>]

Hi everyone,

this is my very first post on this list so I apologise if this has been 
asked before but I couldn't find anything relevant on the web...

I followed the example found here : 
https://github.com/jgrapht/jgrapht/wiki/LabeledEdges but I am getting 
the following output:

//I have replaced /"is a friend of"/ with "likes" & /"is an enemy of"/ 
with "hates"

_John likes John_
John hates John
_John likes James_
John hates James
_John likes Sarah_
John hates Sarah
_John likes Jessica_
John hates Jessica
James likes John
_James hates John_
_Jessica likes James_
Jessica hates James
_Jessica likes Sarah_
Jessica hates Sarah
Sarah likes James
_Sarah hates James_

Surely something is wrong here... For starters, I should only have 8 
edges, not 16 and simply  doing graph.edgeSet() does confirm 8 edges! 
But the loop prints 16 and I have no idea where the non-underlined ones 
come from...

Has anyone else run into this? I am extremely confused...I'm trying to 
get up to speed with JGraphT but such a simple example fails miserably... :(

thanks a lot in advance,

Jim