# All Packages

- Package Summary
  Package | Description
  --- | ---
  org.apache.nutch.analysis.lang | Text document language identifier.
  org.apache.nutch.collection | Subcollection is a subset of an index.
  org.apache.nutch.crawl | Crawl control code and tools to run the crawler.
  org.apache.nutch.exchange | Control code for exchange component, which acts in indexing job and decides to which index writer a document should be routed, based on plugins behavior.
  org.apache.nutch.exchange.jexl | Plugin of Exchange component based on JEXL expressions.
  org.apache.nutch.fetcher | The Nutch multi-threaded fetching module
  org.apache.nutch.hostdb |
  org.apache.nutch.indexer | Index content, configure and run indexing and cleaning jobs to add, update, and delete documents from an index.
  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
  org.apache.nutch.indexwriter.cloudsearch |
  org.apache.nutch.indexwriter.csv | Index writer plugin to write a plain CSV file.
  org.apache.nutch.indexwriter.dummy | Index writer plugin for debugging, writes pairs of <action, url> to a text file, action is one of "add", "update", or "delete".
  org.apache.nutch.indexwriter.elastic | Index writer plugin for Elasticsearch.
  org.apache.nutch.indexwriter.kafka | Index writer plugin to produce JSON messages to Kafka.
  org.apache.nutch.indexwriter.opensearch1x | Index writer plugin for OpenSearch.
  org.apache.nutch.indexwriter.rabbit |
  org.apache.nutch.indexwriter.solr | Index writer plugin for Apache Solr.
  org.apache.nutch.metadata | A Multi-valued Metadata container, and set of constant fields for Nutch Metadata.
  org.apache.nutch.microformats.reltag | A microformats Rel-Tag Parser/Indexer/Querier plugin.
  org.apache.nutch.net | Web-related interfaces: URL `filters` and `normalizers`.
  org.apache.nutch.net.protocols | Helper classes related to the `Protocol` interface, see also `org.apache.nutch.protocol`.
  org.apache.nutch.net.urlnormalizer.ajax |
  org.apache.nutch.net.urlnormalizer.basic | URL normalizer performing basic normalizations: remove default ports, e.g., port 80 for `http://` URLs remove needless slashes and dot segments in the path component remove anchors use percent-encoding (only) where needed E.g., `https://www.example.org/a/../b//./select%2Dlang.php?lang=español#anchor` is normalized to `https://www.example.org/b/select-lang.php?lang=espa%C3%B1ol` Optional and configurable normalizations are: convert Internationalized Domain Names (IDNs) uniquely either to the ASCII (Punycode) or Unicode representation, see property `urlnormalizer.basic.host.idn` remove a trailing dot from host names, see property `urlnormalizer.basic.host.trim-trailing-dot`
  org.apache.nutch.net.urlnormalizer.host | URL normalizer renaming hosts to a canonical form listed in the configuration file.
  org.apache.nutch.net.urlnormalizer.pass | URL normalizer dummy which does not change URLs.
  org.apache.nutch.net.urlnormalizer.protocol | URL normalizer to normalize the protocol for all URLs of a given host or domain.
  org.apache.nutch.net.urlnormalizer.querystring | URL normalizer which sort the elements in the query part to avoid duplicates by permutations.
  org.apache.nutch.net.urlnormalizer.regex | URL normalizer with configurable rules based on regular expressions (`Pattern`).
  org.apache.nutch.net.urlnormalizer.slash |
  org.apache.nutch.parse | The `Parse` interface and related classes.
  org.apache.nutch.parse.ext | Parse wrapper to run external command to do the parsing.
  org.apache.nutch.parse.feed | Parse RSS feeds.
  org.apache.nutch.parse.headings | Parse filter to extract headings (h1, h2, etc.) from DOM parse tree.
  org.apache.nutch.parse.html | An HTML document parsing plugin.
  org.apache.nutch.parse.js | Parser and parse filter plugin to extract all (possible) links from JavaScript files and embedded JavaScript code snippets.
  org.apache.nutch.parse.metatags | Parse filter to extract meta tags: keywords, description, etc.
  org.apache.nutch.parse.tika | Parse various document formats with help of Apache Tika.
  org.apache.nutch.parse.zip | Parse ZIP files: embedded files are recursively passed to appropriate parsers.
  org.apache.nutch.parsefilter.debug | Adds serialized DOM to parse data, useful for debugging, to understand how the parser implementation interprets a document (not only HTML).
  org.apache.nutch.parsefilter.naivebayes | Html Parse filter that classifies the outlinks from the parseresult as relevant or irrelevant based on the parseText's relevancy (using a training file where you can give positive and negative example texts see the description of parsefilter.naivebayes.trainfile) and if found irrelevent it gives the link a second chance if it contains any of the words from the list given in parsefilter.naivebayes.wordlist.
  org.apache.nutch.parsefilter.regex | RegexParseFilter.
  org.apache.nutch.plugin | The Nutch `Plugin` System.
  org.apache.nutch.protocol | Classes related to the `Protocol` interface, see also `org.apache.nutch.net.protocols`.
  org.apache.nutch.protocol.file | Protocol plugin which supports retrieving local file resources.
  org.apache.nutch.protocol.ftp | Protocol plugin which supports retrieving documents via the ftp protocol.
  org.apache.nutch.protocol.htmlunit | Protocol plugin which supports retrieving documents via HTTP/HTTPS using Selenium and the HtmlUnitDriver web driver for the for the HtmlUnit headless browser.
  org.apache.nutch.protocol.http | Protocol plugin which supports retrieving documents via the http protocol.
  org.apache.nutch.protocol.http.api | Common API used by HTTP plugins (`http`, `httpclient`, etc.)
  org.apache.nutch.protocol.httpclient | Protocol plugin which supports retrieving documents via the HTTP andHTTPS protocols, optionally with Basic, Digest and NTLM authentication schemes for web server as well as proxy server.
  org.apache.nutch.protocol.interactiveselenium | Protocol plugin which supports retrieving documents using and interacting with Selenium.
  org.apache.nutch.protocol.interactiveselenium.handlers | Handler implementations to interact with Selenium for `org.apache.nutch.protocol.interactiveselenium`.
  org.apache.nutch.protocol.okhttp | Protocol plugin for HTTP/HTTPS based on okhttp, supports HTTP 1.1 and/or http/2.
  org.apache.nutch.protocol.selenium | Protocol plugin which supports retrieving documents via Selenium.
  org.apache.nutch.publisher |
  org.apache.nutch.publisher.rabbitmq | Publisher package to implement queues
  org.apache.nutch.rabbitmq |
  org.apache.nutch.scoring | The `ScoringFilter` interface.
  org.apache.nutch.scoring.depth | Scoring filter to stop crawling at a configurable depth (number of "hops" from seed URLs).
  org.apache.nutch.scoring.link | Scoring filter used in conjunction with `WebGraph`.
  org.apache.nutch.scoring.metadata | Metadata Scoring Plugin
  org.apache.nutch.scoring.opic | Scoring filter implementing a variant of the Online Page Importance Computation (OPIC) algorithm.
  org.apache.nutch.scoring.orphan | Scoring filter to modify score or status of orphaned pages (no inlinks found for a configurable amount of time).
  org.apache.nutch.scoring.similarity |
  org.apache.nutch.scoring.similarity.cosine | Implements the cosine similarity metric for scoring relevant documents
  org.apache.nutch.scoring.similarity.util | Utility package for Lucene functions.
  org.apache.nutch.scoring.urlmeta | URL Meta Tag Scoring Plugin
  org.apache.nutch.scoring.webgraph | Scoring implementation based on link analysis (`LinkRank`), see `WebGraph`.
  org.apache.nutch.segment | A segment stores all data from on generate/fetch/update cycle: fetch list, protocol status, raw content, parsed content, and extracted outgoing links.
  org.apache.nutch.service |
  org.apache.nutch.service.impl |
  org.apache.nutch.service.model.request |
  org.apache.nutch.service.model.response |
  org.apache.nutch.service.resources |
  org.apache.nutch.tools | Miscellaneous tools.
  org.apache.nutch.tools.arc | Tools to read the Arc file format.
  org.apache.nutch.tools.warc | Tools to import / export between Nutch segments and WARC archives.
  org.apache.nutch.urlfilter.api | Generic `URL filter` library, abstracting away from regular expression implementations.
  org.apache.nutch.urlfilter.automaton | URL filter plugin based on dk.brics.automaton Finite-State Automata for JavaTM.
  org.apache.nutch.urlfilter.domain | URL filter plugin to include only URLs which match an element in a given list of domain suffixes, domain names, and/or host names.
  org.apache.nutch.urlfilter.domaindenylist | URL filter plugin to exclude URLs by domain suffixes, domain names, and/or host names.
  org.apache.nutch.urlfilter.fast | URL filter plugin that first does fast exact suffix matches on host/domain names before applying regular expressions to the path component of a URL.
  org.apache.nutch.urlfilter.ignoreexempt | URL filter plugin which identifies exemptions to external urls when when external urls are set to ignore.
  org.apache.nutch.urlfilter.prefix | URL filter plugin to include only URLs which match one of a given list of URL prefixes.
  org.apache.nutch.urlfilter.regex | URL filter plugin to include and/or exclude URLs matching Java regular expressions.
  org.apache.nutch.urlfilter.suffix | URL filter plugin to either exclude or include only URLs which match one of the given (path) suffixes.
  org.apache.nutch.urlfilter.validator | URL filter plugin that validates given urls.
  org.apache.nutch.util | Miscellaneous utility classes.
  org.creativecommons.nutch | Sample plugins that parse and index Creative Commons metadata.