Package org.apache.nutch.indexer

## Interface IndexingFilter

- All Superinterfaces:
    `Configurable`, `Pluggable`
  All Known Implementing Classes:
    `AnchorIndexingFilter`, `Any23IndexingFilter`, `BasicIndexingFilter`, `CCIndexingFilter`, `FeedIndexingFilter`, `GeoIPIndexingFilter`, `JexlIndexingFilter`, `LanguageIndexingFilter`, `LinksIndexingFilter`, `MetadataIndexer`, `MimeTypeIndexingFilter`, `MoreIndexingFilter`, `RelTagIndexingFilter`, `ReplaceIndexer`, `StaticFieldIndexer`, `SubcollectionIndexingFilter`, `TLDIndexingFilter`, `URLMetaIndexingFilter`

      public interface IndexingFilter
      extends Pluggable, Configurable

  Extension point for indexing. Permits one to add metadata to the indexed fields. All plugins found which implement this extension point are run sequentially on the parse.

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `static String` | `X_POINT_ID` | The name of the extension point.

  - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `NutchDocument` | `filter​(NutchDocument doc, Parse parse, Text url, CrawlDatum datum, Inlinks inlinks)` | Adds fields or otherwise modifies the document that will be indexed for a parse.

    - ### Methods inherited from interface org.apache.hadoop.conf.Configurable

      `getConf, setConf`

- - ### Field Detail

    - #### X_POINT_ID

          static final String X_POINT_ID

      The name of the extension point.

  - ### Method Detail

    - #### filter

          NutchDocument filter​(NutchDocument doc,
                               Parse parse,
                               Text url,
                               CrawlDatum datum,
                               Inlinks inlinks)
                        throws IndexingException

      Adds fields or otherwise modifies the document that will be indexed for a parse. Unwanted documents can be removed from indexing by returning a null value.
      Parameters:
        `doc` - document instance for collecting fields
        `parse` - parse data instance
        `url` - page url
        `datum` - crawl datum for the page (fetch datum from segment containing fetch status and fetch time)
        `inlinks` - page inlinks
      Returns:
        modified (or a new) document instance, or null (meaning the document should be discarded)
      Throws:
        `IndexingException` - if an error occurs during during filtering