[Jung-support] [Open Discussion] Unexpected null pointer exception

[SourceForge.net <no...@so...>]

The following forum message was posted by adamjava at http://sourceforge.net/projects/jung/forums/forum/252062/topic/4886373:

Why the line
     [b]       this.addEdge(localE, localSrc, localDst, EdgeType.DIRECTED);[/b]
generates [b]Exception in thread "main" java.lang.NullPointerException[/b]?
None of the variables is null. [b]this[/b] variable is the object of the type
graph, extending [b]DirectedSparseGraph<GV, GE>[/b].
Thanks for any suggestions,
Ad