LinkRank in the o.a.n.scoring.webgraph package calculates a modified
version of pagerank. The WebGraph tool calculates the inlinks and
outlinks to pages. The LinkRank tool uses that to create a PageRank
minus reciprocal links and links in the same domain. The NodeDumper
tool will export the number of inlinks, outlinks, scores, etc. for the
urls. The ScoreUpdater tool will put the LinkRank scores back into the
CrawlDb to be used with fetching and index scoring. All of this is in
the 1.2 branch but it should get you started.