[ 源代码： dirgra ]
软件包：libdirgra-java（0.3-1.1）
Java library providing a simple directed graph implementation
A directed graph (or digraph) is a graph (that is a set of vertices connected by edges), where the edges have a direction associated with them.
This library is currently used in JRuby implementation but it's perfectly reusable for any other project requiring this kind of data structures.