Package org.apache.lucene.index

## Class SortingCodecReader

- java.lang.Object
- - org.apache.lucene.index.IndexReader
  - - org.apache.lucene.index.LeafReader
    - - org.apache.lucene.index.CodecReader
      - - org.apache.lucene.index.FilterCodecReader
        - - org.apache.lucene.index.SortingCodecReader

- All Implemented Interfaces:
    `Closeable`, `AutoCloseable`

      public final class SortingCodecReader
      extends FilterCodecReader

  An `CodecReader` which supports sorting documents by a given `Sort`. This can be used to re-sort and index after it's been created by wrapping all readers of the index with this reader and adding it to a fresh IndexWriter via `IndexWriter.addIndexes(CodecReader...)`. NOTE: This reader should only be used for merging. Pulling fields from this reader might be very costly and memory intensive.
  WARNING: This API is experimental and might change in incompatible ways in the next release.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class org.apache.lucene.index.IndexReader

      `IndexReader.CacheHelper, IndexReader.CacheKey, IndexReader.ClosedListener`

  - ### Field Summary

    - ### Fields inherited from class org.apache.lucene.index.FilterCodecReader

      `in`

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `IndexReader.CacheHelper` | `getCoreCacheHelper()` | Optional method: Return a `IndexReader.CacheHelper` that can be used to cache based on the content of this leaf regardless of deletions.
    `DocValuesProducer` | `getDocValuesReader()` | Expert: retrieve underlying DocValuesProducer
    `StoredFieldsReader` | `getFieldsReader()` | Expert: retrieve underlying StoredFieldsReader
    `Bits` | `getLiveDocs()` | Returns the `Bits` representing live (not deleted) docs.
    `LeafMetaData` | `getMetaData()` | Return metadata about this leaf.
    `NormsProducer` | `getNormsReader()` | Expert: retrieve underlying NormsProducer
    `PointsReader` | `getPointsReader()` | Expert: retrieve underlying PointsReader
    `FieldsProducer` | `getPostingsReader()` | Expert: retrieve underlying FieldsProducer
    `IndexReader.CacheHelper` | `getReaderCacheHelper()` | Optional method: Return a `IndexReader.CacheHelper` that can be used to cache based on the content of this reader.
    `TermVectorsReader` | `getTermVectorsReader()` | Expert: retrieve underlying TermVectorsReader
    `KnnVectorsReader` | `getVectorReader()` | Expert: retrieve underlying VectorReader
    `String` | `toString()` |
    `static CodecReader` | `wrap​(CodecReader reader, Sorter.DocMap docMap, Sort sort)` | Expert: same as `wrap(org.apache.lucene.index.CodecReader, Sort)` but operates directly on a `Sorter.DocMap`.
    `static CodecReader` | `wrap​(CodecReader reader, Sort sort)` | Return a sorted view of `reader` according to the order defined by `sort` .

    - ### Methods inherited from class org.apache.lucene.index.FilterCodecReader

      `checkIntegrity, doClose, document, getDelegate, getFieldInfos, getTermVectors, maxDoc, numDocs, unwrap`

    - ### Methods inherited from class org.apache.lucene.index.CodecReader

      `getBinaryDocValues, getByteVectorValues, getFloatVectorValues, getNormValues, getNumericDocValues, getPointValues, getSortedDocValues, getSortedNumericDocValues, getSortedSetDocValues, searchNearestVectors, searchNearestVectors, storedFields, terms, termVectors`

    - ### Methods inherited from class org.apache.lucene.index.LeafReader

      `docFreq, getContext, getDocCount, getSumDocFreq, getSumTotalTermFreq, postings, postings, searchNearestVectors, searchNearestVectors, totalTermFreq`

    - ### Methods inherited from class org.apache.lucene.index.IndexReader

      `close, decRef, document, document, ensureOpen, equals, getRefCount, getTermVector, hasDeletions, hashCode, incRef, leaves, notifyReaderClosedListeners, numDeletedDocs, registerParentReader, tryIncRef`

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

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Method Detail

    - #### wrap

          public static CodecReader wrap​(CodecReader reader,
                                         Sort sort)
                                  throws IOException

      Return a sorted view of `reader` according to the order defined by `sort` . If the reader is already sorted, this method might return the reader as-is.
      Throws:
        `IOException`

    - #### wrap

          public static CodecReader wrap​(CodecReader reader,
                                         Sorter.DocMap docMap,
                                         Sort sort)

      Expert: same as `wrap(org.apache.lucene.index.CodecReader, Sort)` but operates directly on a `Sorter.DocMap`.

    - #### getPostingsReader

          public FieldsProducer getPostingsReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying FieldsProducer
      Overrides:
        `getPostingsReader` in class `FilterCodecReader`

    - #### getFieldsReader

          public StoredFieldsReader getFieldsReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying StoredFieldsReader
      Overrides:
        `getFieldsReader` in class `FilterCodecReader`

    - #### getLiveDocs

          public Bits getLiveDocs()

      Description copied from class: `LeafReader`
      Returns the `Bits` representing live (not deleted) docs. A set bit indicates the doc ID has not been deleted. If this method returns null it means there are no deleted documents (all documents are live).

      The returned instance has been safely published for use by multiple threads without additional synchronization.

      Overrides:
        `getLiveDocs` in class `FilterCodecReader`

    - #### getPointsReader

          public PointsReader getPointsReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying PointsReader
      Overrides:
        `getPointsReader` in class `FilterCodecReader`

    - #### getVectorReader

          public KnnVectorsReader getVectorReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying VectorReader
      Overrides:
        `getVectorReader` in class `FilterCodecReader`

    - #### getNormsReader

          public NormsProducer getNormsReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying NormsProducer
      Overrides:
        `getNormsReader` in class `FilterCodecReader`

    - #### getDocValuesReader

          public DocValuesProducer getDocValuesReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying DocValuesProducer
      Overrides:
        `getDocValuesReader` in class `FilterCodecReader`

    - #### getTermVectorsReader

          public TermVectorsReader getTermVectorsReader()

      Description copied from class: `CodecReader`
      Expert: retrieve underlying TermVectorsReader
      Overrides:
        `getTermVectorsReader` in class `FilterCodecReader`

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`

    - #### getCoreCacheHelper

          public IndexReader.CacheHelper getCoreCacheHelper()

      Description copied from class: `LeafReader`
      Optional method: Return a `IndexReader.CacheHelper` that can be used to cache based on the content of this leaf regardless of deletions. Two readers that have the same data but different sets of deleted documents or doc values updates may be considered equal. Consider using `IndexReader.getReaderCacheHelper()` if you need deletions or dv updates to be taken into account.

      A return value of `null` indicates that this reader is not suited for caching, which is typically the case for short-lived wrappers that alter the content of the wrapped leaf reader.

      Specified by:
        `getCoreCacheHelper` in class `LeafReader`

    - #### getReaderCacheHelper

          public IndexReader.CacheHelper getReaderCacheHelper()

      Description copied from class: `IndexReader`
      Optional method: Return a `IndexReader.CacheHelper` that can be used to cache based on the content of this reader. Two readers that have different data or different sets of deleted documents will be considered different.

      A return value of `null` indicates that this reader is not suited for caching, which is typically the case for short-lived wrappers that alter the content of the wrapped reader.

      Specified by:
        `getReaderCacheHelper` in class `IndexReader`

    - #### getMetaData

          public LeafMetaData getMetaData()

      Description copied from class: `LeafReader`
      Return metadata about this leaf.
      Overrides:
        `getMetaData` in class `FilterCodecReader`