Class Lucene40StoredFieldsFormat

Lucene 4.0 Stored Fields Format.

Stored fields are represented by two files:

  1. The field index, or .fdx file.

    This is used to find the location within the field data file of the fields of a particular document. Because it contains fixed-length data, this file may be easily randomly accessed. The position of document n 's field data is the Uint64 (WriteInt64(Int64)) at n*8 in this file.

    This contains, for each document, a pointer to its field data, as follows:

  2. The field data, or .fdt file.

    This contains the stored fields of each document, as follows:

    • FieldData (.fdt) --> <Header>, <DocFieldData> SegSize
    • Header --> CodecHeader (WriteHeader(DataOutput, String, Int32))
    • DocFieldData --> FieldCount, <FieldNum, Bits, Value> FieldCount
    • FieldCount --> VInt (WriteVInt32(Int32))
    • FieldNum --> VInt (WriteVInt32(Int32))
    • Bits --> Byte (WriteByte(Byte))
      • low order bit reserved.
      • second bit is one for fields containing binary data
      • third bit reserved.
      • 4th to 6th bit (mask: 0x7<<3) define the type of a numeric field:
        • all bits in mask are cleared if no numeric field at all
        • 1<<3: Value is Int
        • 2<<3: Value is Long
        • 3<<3: Value is Int as Float (as of
        • 4<<3: Value is Long as Double (as of
    • Value --> String | BinaryValue | Int | Long (depending on Bits)
    • BinaryValue --> ValueSize, < Byte (WriteByte(Byte)) >^ValueSize
    • ValueSize --> VInt (WriteVInt32(Int32))

This is a Lucene.NET EXPERIMENTAL API, use at your own risk
Inheritance
System.Object
StoredFieldsFormat
Lucene40StoredFieldsFormat
Namespace: Lucene.Net.Codecs.Lucene40
Assembly: Lucene.Net.dll
Syntax
public class Lucene40StoredFieldsFormat : StoredFieldsFormat

Constructors

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Lucene40StoredFieldsFormat()

Sole constructor.

Declaration
public Lucene40StoredFieldsFormat()

Methods

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FieldsReader(Directory, SegmentInfo, FieldInfos, IOContext)

Declaration
public override StoredFieldsReader FieldsReader(Directory directory, SegmentInfo si, FieldInfos fn, IOContext context)
Parameters
Type Name Description
Directory directory
SegmentInfo si
FieldInfos fn
IOContext context
Returns
Type Description
StoredFieldsReader
Overrides
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FieldsWriter(Directory, SegmentInfo, IOContext)

Declaration
public override StoredFieldsWriter FieldsWriter(Directory directory, SegmentInfo si, IOContext context)
Parameters
Type Name Description
Directory directory
SegmentInfo si
IOContext context
Returns
Type Description
StoredFieldsWriter
Overrides