# Package org.apache.nutch.indexer

package org.apache.nutch.indexer
Index content, configure and run indexing and cleaning jobs to add, update, and delete documents from an index. Two tasks are delegated to plugins:

- indexing filters, which fill index fields of each document
- index writer plugins; which send documents to index back-ends (Solr, etc.).

- Related Packages
  Package
  Description
  org.apache.nutch.indexer.anchor
  An indexing plugin for inbound anchor text.
  org.apache.nutch.indexer.arbitrary
  Indexing filter to add document arbitrary data to the index from the output of a user-specified class.
  org.apache.nutch.indexer.basic
  A basic indexing plugin, adds basic fields: url, host, title, content, etc.
  org.apache.nutch.indexer.feed
  Indexing filter to index meta data from RSS feeds.
  org.apache.nutch.indexer.filter
  org.apache.nutch.indexer.geoip
  This plugin implements an indexing filter which takes advantage of the GeoIP2-java API.
  org.apache.nutch.indexer.jexl
  This plugin implements a dynamic indexing filter which uses JEXL expressions to allow filtering based on the page's metadata
  org.apache.nutch.indexer.links
  org.apache.nutch.indexer.metadata
  Indexing filter to add document metadata to the index.
  org.apache.nutch.indexer.more
  A more indexing plugin, adds "more" index fields:last modified date, MIME type, content length.
  org.apache.nutch.indexer.replace
  Indexing filter to allow pattern replacements on metadata.
  org.apache.nutch.indexer.staticfield
  A simple plugin called at indexing that adds fields with static data.
  org.apache.nutch.indexer.subcollection
  Indexing filter to assign documents to subcollections.
  org.apache.nutch.indexer.tld
  Top Level Domain Indexing plugin.
  org.apache.nutch.indexer.urlmeta
  URL Meta Tag Indexing Plugin
- Class
  Description
  CleaningJob
  The class scans CrawlDB looking for entries with status DB_GONE (404) or DB_DUPLICATE and sends delete requests to indexers for those documents.
  CleaningJob.DBFilter
  CleaningJob.DeleterReducer
  IndexerMapReduce
  This class is typically invoked from within `IndexingJob` and handles all MapReduce functionality required when undertaking indexing.
  IndexerMapReduce.IndexerMapper
  IndexerMapReduce.IndexerReducer
  IndexerOutputFormat
  IndexingException
  IndexingFilter
  Extension point for indexing.
  IndexingFilters
  Creates and caches `IndexingFilter` implementing plugins.
  IndexingFiltersChecker
  Reads and parses a URL and run the indexers on it.
  IndexingJob
  Generic indexer which relies on the plugins implementing IndexWriter
  IndexWriter
  IndexWriterConfig
  IndexWriterParams
  IndexWriters
  Creates and caches `IndexWriter` implementing plugins.
  NutchDocument
  A `NutchDocument` is the unit of indexing.
  NutchField
  This class represents a multi-valued field with a weight.
  NutchIndexAction
  A `NutchIndexAction` is the new unit of indexing holding the document and action information.