# Package org.apache.nutch.scoring.webgraph

package org.apache.nutch.scoring.webgraph
Scoring implementation based on link analysis (`LinkRank`), see `WebGraph`.

- Related Packages
  Package
  Description
  org.apache.nutch.scoring
  The `ScoringFilter` interface.
- Classes
  Class
  Description
  LinkDatum
  A class for holding link information including the url, anchor text, a score, the timestamp of the link and a link type.
  LinkDumper
  The LinkDumper tool creates a database of node to inlink information that can be read using the nested Reader class.
  LinkDumper.Inverter
  Inverts outlinks from the WebGraph to inlinks and attaches node information.
  LinkDumper.Inverter.InvertMapper
  Wraps all values in ObjectWritables.
  LinkDumper.Inverter.InvertReducer
  Inverts outlinks to inlinks while attaching node information to the outlink.
  LinkDumper.LinkNode
  Bean class which holds url to node information.
  LinkDumper.LinkNodes
  Writable class which holds an array of LinkNode objects.
  LinkDumper.Merger
  Merges LinkNode objects into a single array value per url.
  LinkDumper.Reader
  Reader class which will print out the url and all of its inlinks to system out.
  LinkRank
  Node
  A class which holds the number of inlinks and outlinks for a given url along with an inlink score from a link analysis program and any metadata.
  NodeDumper
  A tools that dumps out the top urls by number of inlinks, number of outlinks, or by score, to a text file.
  NodeDumper.Dumper
  Outputs the hosts or domains with an associated value.
  NodeDumper.Dumper.DumperMapper
  Outputs the host or domain as key for this record and numInlinks, numOutlinks or score as the value.
  NodeDumper.Dumper.DumperReducer
  Outputs either the sum or the top value for this record.
  NodeDumper.Sorter
  Outputs the top urls sorted in descending order.
  NodeDumper.Sorter.SorterMapper
  Outputs the url with the appropriate number of inlinks, outlinks, or for score.
  NodeDumper.Sorter.SorterReducer
  Flips and collects the url and numeric sort value.
  NodeReader
  Reads and prints to system out information for a single node from the NodeDb in the WebGraph.
  ScoreUpdater
  Updates the score from the WebGraph node database into the crawl database.
  ScoreUpdater.ScoreUpdaterMapper
  Changes input into ObjectWritables.
  ScoreUpdater.ScoreUpdaterReducer
  Creates new CrawlDatum objects with the updated score from the NodeDb or with a cleared score.
  WebGraph
  Creates three databases, one for inlinks, one for outlinks, and a node database that holds the number of in and outlinks to a url and the current score for the url.
  WebGraph.OutlinkDb
  The OutlinkDb creates a database of all outlinks.
  WebGraph.OutlinkDb.OutlinkDbMapper
  Passes through existing LinkDatum objects from an existing OutlinkDb and maps out new LinkDatum objects from new crawls ParseData.
  WebGraph.OutlinkDb.OutlinkDbReducer