Package org.apache.nutch.scoring.link

# Class LinkAnalysisScoringFilter

java.lang.Object
org.apache.nutch.scoring.AbstractScoringFilter
org.apache.nutch.scoring.link.LinkAnalysisScoringFilter

All Implemented Interfaces:
  `Configurable`, `Pluggable`, `ScoringFilter`

public class LinkAnalysisScoringFilter extends AbstractScoringFilter

- ## Field Summary

  ### Fields inherited from interface org.apache.nutch.scoring.ScoringFilter

  `X_POINT_ID`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `LinkAnalysisScoringFilter()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `float`
  `generatorSortValue(Text url, CrawlDatum datum, float initSort)`
  This method prepares a sort value for the purpose of sorting and selecting top N scoring pages during fetchlist generation.
  `float`
  `indexerScore(Text url, NutchDocument doc, CrawlDatum dbDatum, CrawlDatum fetchDatum, Parse parse, Inlinks inlinks, float initScore)`
  This method calculates a indexed document score/boost.
  `void`
  `initialScore(Text url, CrawlDatum datum)`
  Set an initial score for newly discovered pages.
  `void`
  `passScoreAfterParsing(Text url, Content content, Parse parse)`
  Currently a part of score distribution is performed using only data coming from the parsing process.
  `void`
  `passScoreBeforeParsing(Text url, CrawlDatum datum, Content content)`
  This method takes all relevant score information from the current datum (coming from a generated fetchlist) and stores it into `Content` metadata.
  `void`
  `setConf(Configuration conf)`

  ### Methods inherited from class org.apache.nutch.scoring.AbstractScoringFilter

  `distributeScoreToOutlinks, getConf, injectedScore, updateDbScore`

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

  ### Methods inherited from interface org.apache.nutch.scoring.ScoringFilter

  `orphanedScore`

- ## Constructor Details

  - ### LinkAnalysisScoringFilter

    public LinkAnalysisScoringFilter()

- ## Method Details

  - ### setConf

    public void setConf(Configuration conf)
    Specified by:
      `setConf` in interface `Configurable`
    Overrides:
      `setConf` in class `AbstractScoringFilter`

  - ### generatorSortValue

    public float generatorSortValue(Text url, CrawlDatum datum, float initSort) throws ScoringFilterException
    Description copied from interface: `ScoringFilter`
    This method prepares a sort value for the purpose of sorting and selecting top N scoring pages during fetchlist generation.
    Specified by:
      `generatorSortValue` in interface `ScoringFilter`
    Overrides:
      `generatorSortValue` in class `AbstractScoringFilter`
    Parameters:
      `url` - url of the page
      `datum` - page's datum, should not be modified
      `initSort` - initial sort value, or a value from previous filters in chain
    Returns:
      a sort value for use in sorting and selecting the top N scoring pages during fetchlist generation
    Throws:
      `ScoringFilterException` - if there is a fatal error preparing the sort value

  - ### indexerScore

    public float indexerScore(Text url, NutchDocument doc, CrawlDatum dbDatum, CrawlDatum fetchDatum, Parse parse, Inlinks inlinks, float initScore) throws ScoringFilterException
    Description copied from interface: `ScoringFilter`
    This method calculates a indexed document score/boost.
    Specified by:
      `indexerScore` in interface `ScoringFilter`
    Overrides:
      `indexerScore` in class `AbstractScoringFilter`
    Parameters:
      `url` - url of the page
      `doc` - indexed document. NOTE: this already contains all information collected by indexing filters. Implementations may modify this instance, in order to store/remove some information.
      `dbDatum` - current page from CrawlDb. NOTE:
      - changes made to this instance are not persisted
      - may be null if indexing is done without CrawlDb or if the segment is generated not from the CrawlDb (via FreeGenerator).
      `fetchDatum` - datum from FetcherOutput (containing among others the fetching status)
      `parse` - parsing result. NOTE: changes made to this instance are not persisted.
      `inlinks` - current inlinks from LinkDb. NOTE: changes made to this instance are not persisted.
      `initScore` - initial boost value for the indexed document.
    Returns:
      boost value for the indexed document. This value is passed as an argument to the next scoring filter in chain. NOTE: implementations may also express other scoring strategies by modifying the indexed document directly.
    Throws:
      `ScoringFilterException` - if there is a fatal error whilst calculating the indexed document score/boost

  - ### initialScore

    public void initialScore(Text url, CrawlDatum datum) throws ScoringFilterException
    Description copied from interface: `ScoringFilter`
    Set an initial score for newly discovered pages. Note: newly discovered pages have at least one inlink with its score contribution, so filter implementations may choose to set initial score to zero (unknown value), and then the inlink score contribution will set the "real" value of the new page.
    Specified by:
      `initialScore` in interface `ScoringFilter`
    Overrides:
      `initialScore` in class `AbstractScoringFilter`
    Parameters:
      `url` - url of the page
      `datum` - new datum. Filters will modify it in-place.
    Throws:
      `ScoringFilterException` - if there is a fatal error setting an initial score for newly discovered pages

  - ### passScoreAfterParsing

    public void passScoreAfterParsing(Text url, Content content, Parse parse) throws ScoringFilterException
    Description copied from interface: `ScoringFilter`
    Currently a part of score distribution is performed using only data coming from the parsing process. We need this method in order to ensure the presence of score data in these steps.
    Specified by:
      `passScoreAfterParsing` in interface `ScoringFilter`
    Overrides:
      `passScoreAfterParsing` in class `AbstractScoringFilter`
    Parameters:
      `url` - page url
      `content` - original content. NOTE: modifications to this value are not persisted.
      `parse` - target instance to copy the score information to. Implementations may modify this in-place, primarily by setting some metadata properties.
    Throws:
      `ScoringFilterException` - if there is a fatal error processing score data in subsequent steps after parsing

  - ### passScoreBeforeParsing

    public void passScoreBeforeParsing(Text url, CrawlDatum datum, Content content) throws ScoringFilterException
    Description copied from interface: `ScoringFilter`
    This method takes all relevant score information from the current datum (coming from a generated fetchlist) and stores it into `Content` metadata. This is needed in order to pass this value(s) to the mechanism that distributes it to outlinked pages.
    Specified by:
      `passScoreBeforeParsing` in interface `ScoringFilter`
    Overrides:
      `passScoreBeforeParsing` in class `AbstractScoringFilter`
    Parameters:
      `url` - url of the page
      `datum` - source datum. NOTE: modifications to this value are not persisted.
      `content` - instance of content. Implementations may modify this in-place, primarily by setting some metadata properties.
    Throws:
      `ScoringFilterException` - if there is a fatal error injecting score information from the current datum into `Content` metadata