Class Lucene80NormsFormat

  • public class Lucene80NormsFormat
    extends NormsFormat
    Lucene 8.0 Score normalization format.

    Encodes normalization values by encoding each value with the minimum number of bytes needed to represent the range (which can be zero).


    1. .nvd: Norms data
    2. .nvm: Norms metadata
    1. The Norms metadata or .nvm file.

      For each norms field, this stores metadata, such as the offset into the Norms data (.nvd)

      Norms metadata (.dvm) --> Header,<Entry>NumFields,Footer

      • Header --> IndexHeader
      • Entry --> FieldNumber, DocsWithFieldAddress, DocsWithFieldLength, NumDocsWithField, BytesPerNorm, NormsAddress
      • FieldNumber --> Int32
      • DocsWithFieldAddress --> Int64
      • DocsWithFieldLength --> Int64
      • NumDocsWithField --> Int32
      • BytesPerNorm --> byte
      • NormsAddress --> Int64
      • Footer --> CodecFooter

      FieldNumber of -1 indicates the end of metadata.

      NormsAddress is the pointer to the start of the data in the norms data (.nvd), or the singleton value when BytesPerValue = 0. If BytesPerValue is different from 0 then there are NumDocsWithField values to read at that offset.

      DocsWithFieldAddress is the pointer to the start of the bit set containing documents that have a norm in the norms data (.nvd), or -2 if no documents have a norm value, or -1 if all documents have a norm value.

      DocsWithFieldLength is the number of bytes used to encode the set of documents that have a norm.

    2. The Norms data or .nvd file.

      For each Norms field, this stores the actual per-document data (the heavy-lifting)

      Norms data (.nvd) --> Header,< Data >NumFields,Footer

      • Header --> IndexHeader
      • DocsWithFieldData --> Bit set of MaxDoc bits
      • NormsData --> byteNumDocsWithField * BytesPerValue
      • Footer --> CodecFooter
    WARNING: This API is experimental and might change in incompatible ways in the next release.
    • Constructor Detail

      • Lucene80NormsFormat

        public Lucene80NormsFormat()
        Sole Constructor