Package org.apache.lucene.index

Class ReaderUtil

java.lang.Object
org.apache.lucene.index.ReaderUtil
public final class ReaderUtil extends Object
Common util methods for dealing with IndexReaders and IndexReaderContexts.
NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

  • Method Details

    • getTopLevelContext

      public static IndexReaderContext getTopLevelContext(IndexReaderContext context)
      Walks up the reader tree and return the given context's top level reader context, or in other words the reader tree's root context.

    • subIndex

      public static int subIndex(int n, int[] docStarts)
      Returns index of the searcher/reader for document n in the array used to construct this searcher/reader.

    • subIndex

      public static int subIndex(int n, List<LeafReaderContext> leaves)
      Returns index of the searcher/reader for document n in the array used to construct this searcher/reader.

    • partitionByLeaf

      public static int[][] partitionByLeaf(ScoreDoc[] hits, List<LeafReaderContext> leaves)
      Partitions global doc IDs from ScoreDoc array by leaf. Extracts doc IDs, sorts them, and partitions across leaves.
      Parameters:
      hits - the ScoreDoc array (typically from TopDocs.scoreDocs)
      leaves - the index reader's leaves
      Returns:
      array indexed by leaf ord, containing global doc IDs for that leaf (empty if no hits)